There’s no other major item most of us own that is as confusing, unpredictable and unreliable as our personal computers. Everybody has questions about them, and we aim to help.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about DOS in Windows Vista, antispyware programs for Vista and the compatibility of the new Microsoft Office with older versions.

I still use several old DOS programs. They work fine in Windows XP, which I believe includes DOS. But will they still work in the new Windows Vista?

Yes, they probably will. Actually, DOS, the old Microsoft operating system that preceded Windows, hasn’t been included in Windows for years. The early versions of Windows were built on top of DOS, so DOS programs could run as they always did.

But Windows XP didn’t really include DOS. Instead, it included some underlying code that allowed old DOS programs to run. Windows Vista uses this same approach. Microsoft says it has even run the DOS version of VisiCalc, the famous pioneering spreadsheet program, on Vista.

Certain DOS programs that require something called “real mode” — direct access to the computer’s hardware — wouldn’t run properly in XP and won’t run properly in Vista, either. But, if your DOS programs run fine in XP, they will likely run fine in Vista.

I recently purchased a new Windows computer with the Windows Vista Home Premium operating system. Do I need to install a third-party Internet security program or is the included Microsoft Security Center adequate?

Despite its name, the Security Center isn’t actually a security program. It is a monitoring feature of Windows that tells you the status of your security programs. Vista does include two important security programs: a firewall; and an antispyware program called Windows Defender. It doesn’t include an antivirus program. I strongly advise you to buy and install a Vista-compatible antivirus program. You may also want to consider buying an antispyware program that is rated higher than the included Windows Defender, such as Spy Sweeper (webroot.com) or Spyware Doctor (pctools.com).

I teach college courses online. My laptop is three years old and I was thinking of buying a new one this year. I am worried about the compatibility of the new Microsoft Office with older versions. Many students are using older computers to do their homework. I need to be able to open all documents they send me and vice versa.

It is true that the standard file format in the new Office 2007 can’t be read by older versions of Office, unless the users of those older versions install conversion software. However, there are two reasons why this shouldn’t be a problem with your new laptop.

First of all, buying a new laptop doesn’t mean you also have to buy or use the latest version of Microsoft Office. The 2003 version of Office for Windows can be installed and used on a new Windows Vista laptop, if you still have the original disks. Secondly, even if you do switch to the new Office 2007, you can set it to always save your files in the older formats.

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Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Corrections & Amplifications:

The anti-spyware program produced by PC Tools is named Spyware Doctor. In an earlier version of this column, the product was mistakenly referred to as Spy Doctor.

Write to Walter S. Mossberg at mossberg@wsj.com

Vista is much prettier than previous versions of Windows. Its icons look better, windows have translucent borders, and items in the taskbar and in folders can display little previews of what they contain. Security is supposedly vastly better; there are some new free, included programs; and fast, universal search is now built in. There are hundreds of other, smaller, improvements and additions throughout the system, including parental controls and even a slicker version of Solitaire.

After months of testing Vista on multiple computers, new and old, I believe it is the best version of Windows that Microsoft has produced. However, while navigation has been improved, Vista isn’t a breakthrough in ease of use. Overall, it works pretty much the same way as Windows XP. Windows hasn’t been given nearly as radical an overhaul as Microsoft just applied to its other big product, Office.

Vista’s Flip 3D feature lets you scroll through images of currently running programs. The sidebar (right) contains miniapplications. The Windows Photo Gallery (left) is for organizing and editing photos.

Nearly all of the major, visible new features in Vista are already available in Apple‘s operating system, called Mac OS X, which came out in 2001 and received its last major upgrade in 2005. And Apple is about to leap ahead again with a new version of OS X, called Leopard, due this spring.

There are some big downsides to this new version of Windows. To get the full benefits of Vista, especially the new look and user interface, which is called Aero, you will need a hefty new computer, or a hefty one that you purchased fairly recently. The vast majority of existing Windows PCs won’t be able to use all of Vista’s features without major hardware upgrades. They will be able to run only a stripped-down version, and even then may run very slowly.

In fact, in my tests, some elements of Vista could be maddeningly slow even on new, well-configured computers.

Also, despite Vista’s claimed security improvements, you will still have to run, and keep updating, security programs, which can be annoying and burdensome. Microsoft has thrown in one such program free, but you will have to buy at least one more. That means that, while Vista has eased some of the burden on users imposed by the Windows security crisis, it will still force you to spend more time managing the computer than I believe people should have to devote.

Here’s a quick guide to the highlights of the new operating system.

Versions and Upgrading

Vista comes in six versions, two of which are primarily aimed at consumers. One, called Home Premium, is the one most consumers will want. It contains the full Aero interface, and it includes the functionality of Windows Media Center and Windows Tablet edition, which have been discontinued as separate products. Home Premium costs $239, or $159 if you are upgrading from an earlier version of Windows. It will come preloaded on most midrange and some high-end consumer PCs.

The other main consumer edition of Vista is the stripped-down version, called Home Basic. It includes the improved security and search but leaves out the new Aero interface and the Media Center and Tablet functions. It will be preloaded on low-price PCs. Home Basic will cost $199, or $100 for upgraders.

A third version, called Ultimate, will wrap up everything in Home Premium with some additional features from the business versions of Vista. This is for power users, and it is likely to be preloaded on high-end PCs. But some regular users may need Vista Ultimate if their companies have particular network configurations that make it impossible to connect to the company network from home with Home Basic or Home Premium. Vista Ultimate will cost $399, or $259 as an upgrade.

Even if you buy the Home Premium or Ultimate editions, Vista will revert to the Basic features if it detects that your machine is too wimpy to run the new user interface.

For most users who want Vista, I strongly recommend buying a new PC with the new operating system preloaded. I wouldn’t even consider trying to upgrade a computer older than 18 months, and even some of them may be unsuitable candidates. Microsoft offers a free, downloadable Upgrade Advisor program that can tell you how ready your XP machine is. It’s available at: microsoft.com/windowsvista/getready/upgradeadvisor.

If you bought a PC in the past few months, and it had a “Vista Capable” sticker on it, it should be able to run at least Home Basic. If it was labeled “Premium Ready,” it should be able to handle Premium and probably Ultimate.

Microsoft says that Home Basic can run on a PC with half a gigabyte of memory and that Premium and Ultimate will work on a PC with one gigabyte of memory. I strongly advise doubling those numbers. To get all the features of Vista, you should have two gigabytes of memory, far more than most people own.

Even more important is your graphics card, a component most people know little about. Home Basic can run on almost any graphics system. But Premium and Ultimate will need a powerful, modern graphics system to run well.

Performance

I tested Vista on three computers. On a new, top-of-the-line Hewlett-Packard laptop, with Vista preinstalled, it worked smoothly and quickly. It was a pleasure.

On a three-year-old H-P desktop, a Vista upgrade installed itself fine. But even though this computer had a full gigabyte of memory and what was once a high-end graphics card, Vista Ultimate reverted to the Basic user interface. And even then, it ran so slowly and unsteadily as to make the PC essentially unusable.

The third machine was a new, small Dell XPS M1210 laptop. In general, Vista ran smoothly and well on this Dell, but some operations were annoyingly slow, including creating a new message in the built-in Windows Mail program. This surprised me, because the Dell had two gigabytes of memory and a fast processor.

Security

Microsoft says Vista is much more secure than any other operating system. But this is hard to prove, especially at the beginning of its life, when few hackers and malefactors have access to it. One visible security feature asks for your permission before you do potentially dangerous tasks, like installing new software. This is a good thing, and it’s been on the Macintosh for years. But unlike the Mac version, the Vista version of this permission feature doesn’t necessarily require you to type in a password, so a stranger or a child using your PC could grant permission for something you yourself might not allow.

Vista also has built-in parental controls so you can restrict what a child can do on the computer. This is also already on the Macintosh, though the Vista controls are more elaborate.

Microsoft includes a free antispyware program in Vista, called Windows Defender. But PC Magazine regards it as inferior to paid programs like Spy Sweeper and Spy Doctor. So you may want to buy one of these. You should also buy an antivirus program, which isn’t included.

User Interface

The new Aero interface is lovely, and it makes using a PC more pleasant and efficient. It apes some elements on the Macintosh but retains a distinct look and feel. Icons of folders look three dimensional, and they pop. Most file icons are thumbnails that show a tiny preview of the underlying document.

Like the rest of Vista, the Start Menu has a prettier, more refined look.

The old hourglass icon that appeared during delays has been replaced by a gleaming, spinning blue circle. The cutesy names for standard folders, like “My Pictures,” have been changed to simpler ones, like “Pictures.”

As on the Mac, you can now drag favorite folders into a list at the left of open windows, so it’s easy to get to them.

A new feature called Flip 3D shows a 3D view of all the programs you’re running and lets you scroll through them. It’s like the Mac’s excellent Exposé feature, though not quite as handy.

Another new feature, called the Sidebar, is a vertical strip at the side of the screen that can contain tiny programs, called Gadgets, displaying things like favorite photos, news headlines, stock prices and the weather. Once again, this is awfully similar to a Macintosh feature called Dashboard, which displays tiny programs called Widgets.

Some familiar Windows features have new names. The old Display control panel, where you chose screen savers and desktop pictures, is now called Personalization. The Add or Remove Programs control panel is now called Programs and Features.

Search

Like the Mac, Windows now has rapid, universal, built-in search, a very welcome thing. The main search box is contained at the bottom of the Start menu, and it works well. Other search boxes appear in every open window.

You can also save searches as virtual folders, which will keep collecting files that meet your search criteria. This is another feature introduced earlier by Apple.

Built-In Programs

The Outlook Express email program has been given a face-lift and renamed Windows Mail. But it’s pretty much the same, except for a new junk-mail filter. The Windows Address Book has been renamed Windows Contacts and, oddly, turned into a sort of file folder.

The latest version of the Internet Explorer Web browser, with tabbed browsing, is included, though it’s also available for Windows XP.

As on the Mac, Windows now has a nice, centralized Calendar program. And there’s a new photo-organizing program, Windows Photo Gallery, but it’s inferior to Apple’s iPhoto because it doesn’t allow you to create photo books, or add music to slide shows. There’s also a pretty rudimentary DVD-burning program.

The familiar WordPad program can no longer open Microsoft Word files (ironically, Apple’s free built-in word processor does).

Gradually, all Windows computers will be Vista computers, and that’s a good thing, if only for security reasons. But you may want to keep your older Windows XP box around awhile longer, until you can afford new hardware that can handle Vista.

• Email me at mossberg@wsj.com.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about deleting groups of emails on a Treo, eliminating unnecessary background programs and sending files from a Mac to a Windows PC.

How do I delete groups of email messages quickly on the Treo smartphone?

It depends on which Treo model you are using and which email program you are using. If it’s a Windows-based Treo, like the Treo 700w or 700wx, you can’t delete large groups of messages very quickly in the built-in email program. You have to manually select large groups of messages and then use the delete function. If it’s a Treo model that uses the Palm operating system, like the Treo 700p or the 650, it is usually possible to do this automatically with a few keystrokes, though the method varies depending on which email program you are using.

If you are using my favorite Treo email program, SnapperMail, on a Palm-based Treo, and you want to delete all or many of the messages in a mailbox, such as your inbox, you can do so with one hand and as few as three keystrokes. This “Purge” command allows you to delete all the messages, or only messages older than various periods of time you can set. You don’t have to use the stylus, or manually select any messages, or use two hands. You just press the menu button, the “T” key, and the center button on the navigation pad.

When I open the Windows Task Manager, I note that there are anywhere from 52 to 57 “processes” operating on my PC. I am sure this is slowing things down. However, the names of the programs are virtually impossible for a nontechie to understand so I don’t want to eliminate any of them for fear of causing major damage to the operating system. Short of calling a service technician, is there a way for me to find out which processes can be safely shutdown and/or eliminated?

This is one of the major banes of using Windows — every program and even some Web sites think it’s OK to install and run in the background all sorts of little, and not-so-little programs, which create the “processes” you are seeing. Some of them may even be spyware and adware. And, yes, they do slow down your computer.

Unfortunately, I don’t know of any quick, easy way a mainstream, nontechie user can tell which ones can be safely shut down. There are programs like Startup Cop that help you decide which unseen programs you should allow to launch when your computer starts, but they don’t necessarily cover stuff that launches after start-up. And there are Web sites, like processlibrary.com and answersthatwork.com, which let you look up a process to see what it does, but that is a laborious process. The latter Web site offers a $29 program called the Ultimate Troubleshooter for managing all these processes, but it’s pretty intimidating for a nontechie.

Antivirus and antispyware programs can shut down some malicious background processes, or stop them from loading in the first place. But many of the resource-draining “processes” you are finding may be from “legitimate” programs on your PC that simply want to hog the computer.

If I switch from Windows to a Macintosh, will my colleagues be able to read any Mac files I send them?

There is no such thing as a “Mac file.” The Macintosh today can create and read all the major standard types of files that Windows PCs use. For instance, photos in the common JPG format; music files in the common MP3 format; Adobe PDF files; text files; and many other types of files can simply be moved between Windows and Mac computers with no conversion necessary. Microsoft Office files, like Word, Excel and PowerPoint documents, can also be shared between the two platforms, without conversion, if you have the Office program suite on both ends. The Mac’s built-in email program, Apple Mail, even has a setting for sending “Windows Friendly” attachments.

There are some specific programs on both platforms that can create proprietary file types not easily opened, or opened at all, on the other platform. Most annoyingly, the Windows and Mac versions of Quicken don’t share a common file format. But now that the new Macs can also run Windows, you can always launch Windows on your Mac in a pinch to run a program that can handle some Windows-only file type.

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Because of the volume of email I receive, I can’t routinely answer individual questions by email, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about antispyware software, Powerline adapters and the Mac mouse button.

I set my parents up with a new Dell PC, and included antispyware software that I run periodically to clean up the computer. I recently discovered they had more than 200 instances of spyware on the machine. This may be because my 81-year-old father surfs porn sites ALL the time (this isn’t a joke). Is there any way to keep his computer bulletproof and safe?

Assuming you can’t dissuade him from the porn sites, which are common sources of spyware and adware, your best option is to switch to a type of antispyware program that blocks the installation and operation of spyware and adware programs as it is happening, rather than waiting until they are installed to clear them out. The best program I have tested of this type is Spy Sweeper from Webroot, but there are others. These types of programs usually aren’t free, but their prices are modest and they would allow your dad to spend his golden years as he sees fit.

Last week, you recommended Powerline adapters that can route an Internet connection over the regular electrical wires in your house. I have two questions about these products. If a home has two different circuit-breaker boxes, can adapters plugged into outlets connected to the different boxes communicate? And, could a neighbor who shares an outside electrical line potentially spy on my Internet usage?

I am not an expert on electrical systems, and neither of these circumstances applied to my tests. So I asked Netgear, the manufacturer of the XE104 adapters I reviewed last week.

The company says that if the two adapters are plugged into outlets that are on totally independent electrical “loops,” they won’t be able to communicate, because the electrical current itself wouldn’t pass between the loops. However, Netgear claims it is “extremely rare” for a home built after 1950 to have two wholly independent loops, even if they have two different circuit-breaker boxes. The company says that, at least in newer homes, separate circuit boxes are often linked.

However, I would add that electrical layouts vary so much that there is no guarantee that any two electrical outlets will have a connection that will work with Powerline adapters. I believe it will work in the vast majority of cases, but not all. In my home, which is 36 years old, the adapters did work between rooms with different circuit-breaker boxes.

On the security issue, the company says it is theoretically possible, but very unlikely, for a neighbor on your same outside electrical line to spy on a network running over your interior electrical wires. To do so, Netgear says, the neighbor’s house and yours would have to lack a filter between them, and those are commonly present. Even then, a nosy neighbor would have to know that you have a Powerline network — and buy a compatible adapter — in order to access your network.

This is likelier, but still not very probable, in an apartment building, because circuits in such buildings are often shared. The company does include optional encryption software for such situations, so that even if a neighbor can snoop on you, he wouldn’t be able to decipher your network traffic.

I am thinking of buying an Apple MacBook, but I notice it only has one button below the touch pad, and no obvious scrolling control. Without buying and using a mouse, how can you right-click and scroll on a Mac laptop?

The Mac operating system and Apple software do in fact support right-clicking, displaying the same sort of pop-up menus that Windows does. However, on a Mac laptop with the single button, the traditional method for right-clicking has been a clumsy one: holding the Control key while clicking the button.

Now, the latest Mac laptops have a much easier and cleverer method for right-clicking: you just place two fingers on the track pad and click the button. It’s fast and easy, though still not as good as if Apple abandoned its odd mouse dogma and simply built dual buttons into its laptops.

Also, the new Mac laptops have a method for scrolling that I find superior to the methods common on Windows laptops: you just place two fingers on the touch pad and drag them up or down together. It quickly becomes second nature.

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Because of the volume of email I receive, I can’t routinely answer individual questions by email, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

Boot Camp may never be final, because Apple plans to roll its functionality into the forthcoming new version of its OS X operating system, called Leopard, which is due out early in 2007, around the same time Microsoft plans to ship Windows Vista. I assume Apple will stop offering Boot Camp as a separate program around that time. The company states that “Boot Camp Beta is preview software licensed for use on a trial basis for a limited time.” That implies to me that it will likely be discontinued when Leopard comes out. This doesn’t necessarily mean existing installations of Windows on Macs will stop functioning, just that new downloads won’t be available.

I do believe that Leopard will allow Vista to run on Macs. However, just like regular Windows PCs, Macs running Vista will be able to use all of its features only if their hardware specs are hefty enough. My quick and dirty assessment is that the Intel-based iMac, MacBook Pro and Mac mini should be able to do so, but only time will tell.

I have a home network of three PCs. Do I have to download antivirus protection software separately for each computer? What about antispyware software?

Yes, you do. Antivirus and antispyware programs work on a computer-by-computer basis. You can’t just install them on your main PC and expect that they will protect all the other machines on your network.

Which pop-up blockers do you recommend?

You don’t really need a separate pop-up blocker anymore. The latest versions of all the major browsers — Internet Explorer, Firefox and Safari — have built-in pop-up blockers. They aren’t perfect, but they work pretty well. You can turn on the blocking functionality from the preferences or options menus. If you need something more, and you are a Windows user, you can download the Google toolbar, which includes a good pop-up blocker. It can be downloaded at toolbar.google.com.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about converting financial records from a PC to a Mac, scheduling anti-spyware scans and burning home videos in VCD format.

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

I am thinking of converting to an Apple machine, to replace my ancient Dell. However, all my financial records are in the Windows version of Quicken, and I need to keep using Quicken to have access to many years of records. I recall you writing earlier that Quicken was one of the products that didn’t convert well to a Macintosh environment. Do you still feel that would be the case?

There is a Macintosh version of Quicken. However, unlike most other software publishers, Intuit, the maker of Quicken, chose to create a Macintosh edition that is very different from its Windows product and uses a different file format. It is possible to convert Windows Quicken files to work on the Mac version, and some readers have reported it went well. But many more have reported problems with the process, which is very time-consuming and can be error-prone. Therefore, I regard Quicken on the Mac as best for somebody who is starting fresh with financial software, and can’t recommend it for somebody like you, who is converting from the Windows version.

As an alternative, you could keep around your old Windows PC for using Quicken. Or, you could try a program called Moneydance (www.moneydance.com), which has compatible versions for both Windows and Mac, claims to be completely portable between platforms and claims to import Quicken data with ease. I haven’t tested Moneydance and can’t verify these claims, or say how it compares with Quicken. But there’s a free trial available.

You suggested running anti-spyware and anti-virus scans nightly. Is there some way to arrange these to run automatically?

Yes. Most such programs have a built-in scheduler where you can specify a frequency and a time of day — say, every day at 4 a.m.

I transfer my home videos from a camcorder and burn them into CDs in the VCD format. My problem is that the video quality deteriorates significantly. The movie looks like an old home video. How do I improve the quality?

It’s difficult because of the format you are using. The VCD format was designed to squeeze large video files, which would normally require the capacity of a DVD disk, into the much smaller space available on a CD. To accomplish this, the format encodes the video at much lower quality than DVDs typically use. As a result, home videos on VCDs can look much worse than they do on camcorder tapes, or than they would if you burned them to DVD, in the format common on DVDs. So, if video quality is important to you, the best suggestion I have is to buy a DVD burner.

Write to Walter S. Mossberg at mossberg@wsj.com

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about switching between software provided by camera companies, Web-based tax-preparation software and scheduling antispyware sweeps.

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

I have been using Olympus digital cameras for years, so I have a library of Olympus digital photos using Olympus software. If I were to switch to a Canon camera, how easy is it to also switch software? Is there an easy way to transfer the Olympus photos into the Canon software?

Unless you are doing something unusual, all your photos from both cameras should be in the standard format called “jpg” and I assume either company’s software can handle all of them. However, I don’t recommend using the software supplied by camera makers. They may be fine at making cameras, but, with the exception of Kodak, they usually create lousy software. Instead, I suggest getting a good, general photo-organizing program, and making that the center for managing your pictures — whatever camera you use.

Every Macintosh computer comes with a superb program called iPhoto for organizing, sharing and editing photos. Windows computers don’t come with anything as good, but you can download a free program called Picasa from Google, at picasa.com. Or, you can download Kodak’s very nice EasyShare software, at Kodak.com. It’s free, comes in versions for both Windows and Mac, and doesn’t require a Kodak camera or printer to use. Paid software that also does the trick on Windows includes ACDSee, at acdsystems.com; and Corel Photo Album, at corel.com.

In 2002, you advised against using Web-based tax-preparation software, writing, “Your tax data are highly sensitive and confidential, and I think the Web is just too susceptible to hackers and crooks to make it a fitting repository for such information.” Do you continue to have these concerns?

Yes. If anything, the incidence of identity theft and other security problems on the Web have grown worse since 2002. I am not criticizing the tax-preparation companies, which I assume have good security. And I am not advising people against normal e-commerce, or the use of credit cards online. But I would be personally loath to put the broad and deep financial information required for a tax filing on a server controlled by someone else and connected to the Internet. I would instead download or buy traditional tax-preparation software, which keeps your data on your own hard disk.

I have the Spy Sweeper antispyware software that you recommend, and am wondering how often you suggest scheduling it to automatically scan my computer for software. I was thinking once a month.

Once a month isn’t good enough if you are an active Internet user, or your computer is on a broadband connection and stays on, and connected, all the time. I run both spyware and virus scans nightly on my Windows computers, and I advise all Windows broadband users to do so. There’s no downside, if your computer is on all the time anyway. I also advise setting the software to run in the background, guarding your PC against new intrusions.

Write to Walter S. Mossberg at mossberg@wsj.com

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about books for switching from Windows PCs to Macintosh, antispyware program and transferring files from an old computer to a new one.

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

I am about to switch to the Macintosh after many years using only Windows PCs. Is there a good book to help me with the transition?

In addition to the many books about how to use a Mac in general, there are two that were written specifically to guide Windows users in making the switch to the Mac’s OS X operating system — though in my experience most Windows users can successfully switch without a book.

One book, called “Switching to the Mac,” is by David Pogue. The second, called “Mac OS X for Windows Users: A Switchers’ Guide,” is by David Coursey. Both authors are veteran technology writers. Neither book takes into account the latest Mac operating system, called Tiger, because they were published before Tiger appeared. But either should still be a strong guide to making the switch. The Pogue book is also slated to be updated next month with a new edition that covers Tiger. Mr. Coursey has also just published “The Mac Mini Guidebook,” which, while focused on Apple’s newest low-end model, has a lot of content on switching and covers Tiger as well.

In addition, there is a wealth of material on Apple’s Web site on how to switch from Windows. An entire section of the site, devoted to switching, can be found at www.apple.com/switch. A basic tutorial on the Mac can be found at www.apple.com/support/mac101.

About a week after I downloaded and installed the Google Toolbar, I noticed a strange looking program had knocked it off to the far right of my screen. I’m sure I unknowingly downloaded this piece of spyware and now it takes over my Google searches. Any suggestions on how to excise it?

You need to obtain and run a good antispyware program, and then keep it running all the time. In fact, at first, you may need to run several of them to expunge this particular piece of malicious software and any others you might have accumulated. My current recommendation in this category is Webroot’s Spy Sweeper, but there are other good ones, including Spybot Search and Destroy, Ad-Aware and CounterSpy.

I have an old Dell computer that I acquired in 1998. I would like to purchase the new eMachines PC recommended in your recent article. My problem is that I would have to transfer my files onto the new computer but my Dell only has a floppy drive and a Zip drive, and the eMachines PC lacks these drives. How can I do this?

You can connect the two computers with a cable and automatically transfer your files using software programs specially designed for this task, such as IntelliMover by Detto (www.detto.com) and Alohabob PC Relocator by Eisenworld (www.alohabob.com). These products usually include cables, but you may have to pay extra for a different cable that works with your old PC.

Another option would be to buy an external USB version of the Zip Drive, install it on the new PC, and then transfer your files via Zip disk. Such an external Zip drive can be bought starting at well under $100. See www.iomega.com.

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Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

In my financial and professional life, I use many password-protected sites. Some force a particular syntax on me, and I am concerned that even if I could use the same password for every situation, it is probably not safe to do so. How do I keep track of all this, without leaving a list somewhere for a hacker to find?

This is a widespread dilemma, and many people cope with it either by using the same few passwords for everything or by keeping a list of passwords in a computer file, or on a piece of paper. Those methods are insecure.

One solution is to use a special program that stores all your passwords in an encrypted file. This file is itself protected by a password, but if you simply memorize that one password, you can refer to all your others whenever you like. There are many such programs, and many are free for individual users, or for up to a modest number of passwords.

Two examples are Any Password, by Roman Lab (www.romanlab.com/a pw/) and Password Agent by Moon Software (www.moonsoftware.com). I haven’t reviewed these and can’t say if they are good. Still, they may be worth a try.

Another option is to buy a fingerprint reader, or a computer with such a reader built in. These devices typically come with software that will store all your passwords in an encrypted file and automatically enter any password when you simply swipe your finger over the reader.

How can I get rid of SearchforFree.info, which has taken over my home page, and return to Google as my home page. I have heard that the former is a hijack. Is there an easy way to return my home page to where I want it?

I’m not familiar with SeachforFree.info, but it has been identified as a browser hijacker — a spyware program that takes over a person’s home page and/or chosen search engine in place of the user’s own choice. The only way I know of to permanently get rid of this kind of program is to run a reputable antispyware program at all times. That should remove it and prevent it from returning. The antispyware program I recommend is Spy Sweeper from Webroot Software (www.webroot.com), but other good antispyware programs also may do the trick. If you try one of them, and it doesn’t work, try another.

I receive spam email daily that displays in the “from” line the names of real people whom I use regularly in my normal outgoing email. I run an antispyware program daily, but the use of these names continues and it’s kind of frightening. Does this happen to everyone?

It happens to a lot of people. Some spammers use malicious software, usually in the form of a virus-laden email, that harvests names from an address book and then uses them as the fake “from” address in spam. They do this so that antispam filters won’t catch the spam, because most filters are set to allow messages from people in your address book or in your sent-message folder to pass through.

In your case, the malicious software or virus may have harvested your own address book, or the address book of one or more of your correspondents, which has many similar entries. Because of this tactic, some people even get spam that they appear to have sent themselves.

Your antispyware software isn’t likely to touch this problem. You need a good antivirus program that scans email, and a good spam filter. Even with those, however, it will be hard or impossible to undo any damage that has been done, especially since the infection may have occurred on a friend’s personal computer, not your own. The best you can do is to look for some identifying characteristic, other than the “from” line, in this troublesome email, and set your antispam filter or the rules in your email program to block messages with that characteristic, regardless of who the sender seemed to be.

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Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

You recently recommended antispyware programs for Windows users. Do Apple Macintosh users need such software, and, if so, what products clean up spyware on the Mac?

There’s little or no reported spyware for Apple’s Mac OS X operating system. So the spyware problem isn’t much of a headache for Mac users, and consequently, there isn’t much of a market for Mac antispyware software.

Most spyware and adware consists of malicious programs, and, like regular programs, these harmful applications have to be written to run on a particular operating system. All the spyware programs I have seen, or heard about, are written to run on Windows, which is on the vast majority of the world’s PCs, and is also easier for spyware programs to penetrate than the Mac operating system is. Because they are Windows programs, they simply won’t run on the Mac, even if Mac users accidentally download them.

One type of spyware, called tracking cookies, doesn’t take the form of an actual program, and can be used on Macs. There are a few antispyware and cookie-control utilities for the Mac that may be effective against these tracking cookies, such as Internet Cleanup from Allume Software (www.allume.com). But, unlike their Windows counterparts, I haven’t tested any of them, and can’t say how well they work.

Mac users who run Apple’s built-in Safari Web browser can stop most tracking cookies by going to the Security portion of the Preferences panel and selecting the option to accept only cookies placed by the site they are using, which eliminates cookies placed by third-party advertising companies. A similar option is available in the Firefox Web browser, on both Mac and Windows. On the Mac, it’s in Firefox’s Preferences panel, under Privacy.

I’m at a loss as to where to find blogs on the Web. Are there blog search engines that help compile and categorize blogs for public perusal?

Yes. You can search or browse Web logs, or blogs, at several sites such as Feedster (feedster.com), Bloglines (bloglines.com) and Technorati (technorati.com).

You can also install special programs that let you find, and subscribe free of charge, to numerous blogs and other frequently updated Web sites. These include FeedDemon for Windows (feeddemon.com) and NetNewsWire on the Mac (ranchero.com/net newswire/).

With these programs, called news readers, you don’t usually see the blog in its original form, you receive “feeds” from them — constantly updated headlines and summaries of new entries. You can then read the entire item by just clicking on the headline.

I’ve been shopping for a TV that can receive broadcast high-definition signals, and notice many described as “HD-ready.” What does that mean?

To receive and display high-definition programming, a TV set needs two basic features. One is a display capable of rendering the high-definition picture. The other is a tuner, or receiver, capable of receiving the high-definition signal, either over the air, or from a cable or satellite service.

When a TV set is described as “HD-ready,” it usually means the set can display high-definition pictures, but lacks the special tuner needed to receive them. It may have no tuner at all built in, or it may have just a standard tuner. With this type of TV, you must buy a separate high-definition over-the-air tuner, or obtain a high-definition cable or satellite receiver, to get high-definition programming.

* * *

Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

I am moving from an old Dell with Windows XP to a new one. I want to move over a wonderful picture of a covered bridge that I use for my desktop. It has family significance, and it’s my only copy. But, I can’t find the bridge picture anywhere. I didn’t keep all my photos in the “My Pictures” folder and have no idea where they all are.

If you go to the Display control panel, select the Desktop tab and highlight the name of your bridge picture (which should be listed there), and then click on Browse, you may see the folder where the picture resides.

This doesn’t always work. If it doesn’t, because this picture has personal significance for you, I suspect it would be worth it for you to spend some time and effort to conduct a thorough search. And, since the built-in search in Windows is awful, I suggest you download and install one of two free search programs that can find pictures anywhere on your hard disk and show you a preview of them.

Both Yahoo Desktop Search (at desktop.yahoo.com) and MSN Desktop Search (at toolbar.msn.com) meet that description (the popular Google desktop search has no preview feature). They require time to index your hard disk, but, once they do so, they should be able to locate and find your bridge picture.

Is there any way I can copy the address book used by Outlook Express so I can move it to a second computer?

Yes. The address book is contained in a file whose name is usually your user name, followed by a period and the letters “WAB,” for Windows Address Book. It usually resides deep in a subfolder in the Documents and Settings folder.

To find it, use the built-in Windows search system (it’s weak, but can do this particular task) or a third-party search program to search for “WAB” or “.WAB”. It should come up. Once you find it, you can just copy it like any file to a removable medium, like a writable CD or a USB thumb drive, or even email it to yourself.

When you copy it to your new computer, remember where you placed it. Then, open Outlook Express on the second computer, and open the address book by going to the Tools menu and clicking on Address Book. Go to the address book’s File menu, select Import, and click Address Book (WAB). Navigate to the address-book file that you copied from the first PC, and then click Open.

Why do you recommend using antispyware software to get rid of tracking cookies? Isn’t it more effective to just use the cookie-management features of a Web browser to delete these cookies or block them in the first place?

No. The cookie-management features in popular browsers don’t distinguish between tracking cookies, a type of spyware that records your activities online, and the many helpful cookies you probably want to keep, like those that store your login information or preferences on a site. Some allow you to block or delete only “third-party” cookies, which might trap some tracking cookies placed by Internet advertising firms who aren’t the actual operators of the Web sites you visit. But this may not always work.

Instead, I recommend using a good antispyware program, which every Windows user should be running anyway. These programs aren’t focused on cookies in general, but on every kind of computer code, including tracking cookies, that qualify as spyware and adware. They detect tracking cookies by maintaining lists of the most common ones, and they update this information constantly. They leave nontracking cookies alone.

Of course, you could use both methods. You could set your browser to reject third-party cookies (assuming that this doesn’t impair your browsing experience) and still run regular spyware scans to catch any tracking cookies that still make it through.

Write to Walter S. Mossberg at mossberg@wsj.com

You would likely be outraged at this violation of privacy. Yet that kind of Big Brother intrusion goes on every day on the Internet, affecting millions of people. Many Web sites, even from respectable companies, place a secret computer file called a “tracking cookie” on your hard disk. This file records where you go on the Web on behalf of Internet advertising companies that later use the information for their own business purposes. In almost all cases, the user isn’t notified of the download of the tracking cookie, let alone asked for permission to install it.

Luckily, the leading Windows antispyware programs can detect and remove these tracking cookies. It is the best defense a user has against this tactic.

Now, though, some of the companies that place these files on your hard disk are complaining about that defense. Some are urging the antispyware software companies to stop detecting and removing tracking cookies. They assert that the secret placement of these tracking mechanisms is a legitimate business practice, and that tracking cookies aren’t really spyware or aren’t harmful.

Unfortunately for consumers, this twisted reasoning is having some impact. In the most notable case, Microsoft disabled the detection and removal of tracking cookies when it purchased an antispyware program from a small company called Giant and turned it into Microsoft Windows AntiSpyware. That is a big reason why I can’t recommend the Microsoft product, which still is in the test phase but is available for anyone to download.

Microsoft says it still is evaluating how to treat tracking cookies in the program’s final release. I believe it is important for consumers to know who is on their side right from the start and who may be being swayed by companies that do things to your computer without telling you.

The antispyware program I currently use and recommend, Spy Sweeper from Webroot Software, still detects and removes tracking cookies. So does another antispyware program derived from some of the same computer code as the Microsoft product — CounterSpy, by Sunbelt Software. I haven’t tested the latter program, but it has received good reviews elsewhere. There are other antispyware programs as well that still treat tracking cookies as spyware.

To understand the tracking-cookie issue, you have to know something about cookies overall, and you have to know what spyware actually is.

Cookies are small text files that Web-site operators — and third-party companies that insert ads into Web sites — place on a user’s computer. Many types of cookies are harmless or even helpful. For instance, a cookie might help a Web site remember your preferences for what news topics you chose to see. With your permission, it might store your login information, so you don’t have to type it in each time you visit a particular site. Antispyware programs aren’t designed to detect or remove these helpful cookies.

Tracking cookies shouldn’t be confused with these other cookies. They have no user benefit except the vague promise that the ads you get as a result may be better tailored to your interests.

What is spyware? There are many definitions, but here is mine, in two sentences. Spyware — and a related category called adware — is computer code placed on a user’s computer without his or her permission and without notification, or with notification so obscure it hardly merits the term. Once installed, spyware and adware alter the PC’s behavior to suit the interests of outside parties rather than those of the owner or user.

Examples of spyware and adware include programs called “browser hijackers,” which reset the home page or search engine used by your browser so the user is diverted to the sites of the spyware and adware companies or their clients. Others record your activities and report them to outside parties. Still others push ads in your face, even when you aren’t using the Web.

Some tracking-cookie purveyors say their cookies aren’t really spyware because they aren’t full-fledged programs and they aren’t as outrageous as spyware programs like “key loggers,” which record and report every keystroke you enter. Others argue that the companies don’t collect personally identifiable data, only aggregate data from many users. To me, tracking cookies clearly meet the obvious definition of spyware.

Rather than trying to legitimize tracking cookies with pressure and marketing campaigns, I suggest that, if they really believe tracking cookies are legitimate, the companies that use them simply go straight. They should ask a user’s permission to install the cookies, pointing out whatever user benefits they believe the cookies provide. They might even offer users compensation for allowing tracking cookies on their machines.

Until that happens, here is my advice: If you don’t like the idea of tracking cookies, run an antispyware program that detects and removes them, along with all the other indefensible computer code some companies think they have the right to install. After all, it is your computer.

Write to Walter S. Mossberg at mossberg@wsj.com

There have long been computer viruses, but until the past couple of years, they were mainly a nuisance. Now they have grown into a serious problem — by one account there were 5,000 new Windows viruses discovered in the first six months of 2004. And the virus plague has been trumped by a new type of malicious software, spyware, which can track your activities, bombard you with unwanted ads, even steal your identity.

Spam has also grown exponentially, clogging e-mail boxes and carrying with it malicious software. For some people, e-mail has become a curse.

And that’s not all. Every minute of every day, hackers using automated software scan the Internet looking for computers vulnerable enough to invade and, in some cases, to surreptitiously take over. Without your knowledge, they can turn your computer into a “zombie” machine rigged to help them spread their nasty viruses, spam and spyware.

So for consumers and small businesses — everyone without a large IT department to manage security — the Windows computers they use have become huge burdens instead of helpful tools. If you do get a severe virus or spyware infestation, you may have to spend hundreds of dollars and many hours to wipe your hard disk clean and start fresh, quite possibly losing crucial data in the process.

And prevention is almost as painful as the disease, because the computer industry has so far come up with only half-baked and piecemeal solutions to these threats. You have to watch every move you make online and install a bunch of security programs, which require monitoring, constant updating and, often, annual fees.

Each of these security programs deals only with a narrow slice of the problem. Firewalls can keep out invaders, but they don’t stop viruses, spyware or spam. Antivirus programs don’t catch most spyware. Antispyware programs don’t stop viruses. And neither stops spam. For that, you need anti-spam software, which does nothing about viruses or spyware that invade your system through avenues other than spam.

You can buy “suites” that combine all these programs, but they are really just bundles of separate applications of widely varying quality stuffed into the same box.

It’s as if you needed a separate burglar alarm system, each with its own control panel, password and monthly fee, for every door and window in your home.

What users need is a simple, all-encompassing security service that would deal with all these threats with minimal user involvement. For now, though, you’ll have to do it yourself.

So here’s my quick guide to Windows security measures. Some of the products I recommend below are free, but others cost money. I like free stuff as much as the next guy, but I don’t believe security is an area where price should govern. You don’t want to entrust your computer’s security to some unknown software author, or even to a well-meaning individual or very small outfit that lacks the resources to keep up with the threats.

Download and install all the security fixes Microsoft issues for Windows. If you have Windows XP, set it to automatically fetch and install these patches (you can do this by clicking on the “Automatic Updates” or “Security Center” icons in the Windows control panel). You should also probably install the massive Service Pack 2 revision of Windows XP, which plugs many security holes. But back up your data first. A significant minority of users have reported big problems with SP2.

Stop using Microsoft’s Internet Explorer Web browser, which has become a four-lane highway for malicious invaders. I recommend instead Mozilla Firefox, which is free at www.mozilla.org [http://www.mozilla.org]. I use it all day, every day.

Windows comes with a firewall program, designed to keep out hackers. But in most versions of the operating system, it’s hard to turn on and configure. Even the improved firewall in the new SP2 revision of Windows XP is inferior to several third-party products. I recommend, and use, ZoneAlarm, a free firewall from Zone Labs, available at www.zonelabs.com [http://www.zonelabs.com]. There are some fancy paid versions of ZoneAlarm, which are also fine, but if you want the free one, you’ll have to look hard on the Web page.

Software to stop spyware is still in its infancy, so I suggest keeping two or three anti-spyware programs on hand. Each program will likely find spyware the others miss. But I recommend relying most on the one I use, Webroot’s Spy Sweeper, available at www.webroot.com [http://www.webroot.com]. It costs $30, including a year of updates, and runs all the time to block incoming spyware. To back up Spy Sweeper, go to www.download.com [http://www.download.com] and get two free programs: Ad-Aware, and Spybot Search and Destroy. Use these for manual scanning.

I recommend Norton AntiVirus from Symantec. It costs $50, including a year of updates. But it works well and has a good automatic updating system. I have been receiving many reports of problems with Symantec’s customer service, so I may have to change my recommendation down the road. But for now, I prefer Norton, and I use it myself.

No antispam program I have tested is wholly satisfying, but I suggest one of two. The first is MailFrontier Desktop, available for $30 at www.mailfrontier.com [http://www.mailfrontier.com]. The second is SpamSubtract, from Intermute, available for $20 at www.spamsubtract [http://www.spamsubtract]. com. They are very different, and each has its strengths and weaknesses. I oscillate between the two every six months or so.

Beyond installing, monitoring and updating all this software, you need to be careful online. Don’t open email attachments you don’t expect and that come from strangers. They may contain viruses or spyware. Don’t download software unless you really need it and are 100 percent certain of the author’s trustworthiness. It could be an infection in disguise. Never click on a link in an e-mail purporting to be from a financial institution, even if it’s your own bank and it looks official. It could be a scam to steal your identity.

And if you’re totally fed up with the security crisis but want to continue using your computer for common tasks, consider dumping Windows altogether and switching to Apple’s Macintosh, which uses its own operating system, called OS X. There has never been a successful virus reported on OS X, and there is little or no spyware for the Mac.

In my view, Macs have better hardware, a better operating system and better bundled software than Windows PCs. They are as good as, and often better than, Windows PCs at e-mail and Web surfing; at word processing and other productivity tasks; and at handling digital photos, videos and music. And most popular Windows file types open right up in Mac programs, without the need for any conversion or translation.

Stay safe out there.