Such a user would be able to upgrade to, and run, both new operating systems on the same Mac. Microsoft says Windows 7 will be licensed to work within a virtual machine on a Mac—a faux Windows computer—just like XP and Vista can. Apple also plans to offer Windows 7 drivers for its hardware after the new Microsoft system comes out on Oct. 22, so that users who wish to use its Boot Camp system for running Windows on a Mac can use the new Windows.

You can choose to keep running older versions of Windows on Macs equipped with Snow Leopard, or, presumably, run Windows 7 on Macs that still run Leopard. But note that if you do upgrade a copy of Windows to Windows 7 running on a Mac—even if it’s in a virtual machine—you must follow the same, sometimes painful, process that faces owners of standard Windows computers.

I am color blind and am wondering if the DriveSharp driving improvement software you reviewed last week involves identifying colors as part of the learning process.

Yes, it does. Both of the program’s training exercises, which hone users’ abilities to track multiple moving objects and to expand their fields of vision, do rely to some extent on distinguishing colors.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital web site, http://walt.allthingsd.com.

To avoid the difficulties you described last week with migrating from Windows XP to Windows 7, what do you think about a two-step approach whereby we buy Vista, upgrade from XP to Vista, and then go from Vista to Windows 7?

That would work, since–unlike those running XP–PCs running Vista can be upgraded to Windows 7 directly, without wiping their hard drives, displacing any files or re-installing any programs.

However, you’d be doing twice the work and paying for two new versions of Windows instead of one.

If I bought a Vista computer, but had it downgraded at the factory to XP, will my situation be any different than what you described should I choose to migrate to Windows 7?

According to Microsoft, the answer is no. Your computer is now a Windows XP computer, and thus still has no direct upgrade path to Windows 7. You would still have to remove and later restore your personal files, wipe your hard disk clean, and then re-install all your programs. However, if you received Windows Vista installation disks with the machine, you could upgrade it to Windows Vista first, and then, upgrade it directly to Windows 7, a process that doesn’t require any of those cumbersome steps.

Does the difficult scenario of moving from Windows XP to Windows 7 that you described last week also apply to those of us who run XP on Macs in virtual-machine programs like Parallels or Fusion?

Yes. Microsoft says the same migration steps are necessary whether the Windows XP computer is physical or virtual, and that includes Macs running XP via the Parallels or Fusion software.

It also applies if you are running XP on a Mac using Apple’s Boot Camp program and wish to move to Windows 7.

After Windows 7 comes out in October, will Microsoft somehow force us XP users to stop using it? Is there any reason I have to upgrade, or can I keep using XP, which meets my needs perfectly?

You can keep using Windows XP and all your current programs on your current computer. It won’t suddenly expire.

Especially in light of how hard it will be to upgrade, can you please explain what advantages Windows 7 will have over XP, which is tried and true? I deliberately skipped Vista and am inclined to skip this new Windows version as well.

People should never feel stampeded to upgrade their technology and should keep using whatever meets their needs and makes them comfortable.

However, based on my testing of pre-release versions of Windows 7, I would say it is significantly better than XP, which, after all, was designed a decade ago, an eternity in computer time.

I’ll cite just a few examples. Microsoft says that Windows 7 is more secure than XP, because its underlying architecture allows more defenses against malicious software than in the older product. Microsoft claims, and my tests bear out, that Windows 7 makes networking computers much simpler, quicker and more reliable than XP does. And the company says that Wi-Fi networks work better and faster than they do with XP.

I would add that, if Windows 7 catches on in a way that Vista didn’t, you may gradually find that new software and hardware makers will stop bothering to make their products compatible with XP, though this process will take years.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital Web site, http://walt.allthingsd.com.

Do you still recommend the Dell XPS One all-in-one computer that you favorably reviewed last December? I am not a techie at all but need to replace my 5-year-old Dell and was interested in an all-in-one.

Yes. In fact, I now own two of these Dell XPS Ones and use them as my Vista desktop computers, at home and in the office. I still believe, as I wrote in my review, that this Dell’s hardware is superior to that of the competing Apple iMac, though the Vista operating system is inferior to Apple’s. And the base XPS One now costs the same as the base iMac — $1,199 — instead of $300 more, as it did last year. So, if you want the Windows operating system, and like the look and convenience of an all-in-one desktop, I still favor the XPS One. You can find my review at tinyurl.com/2xw 6mv.

Will Apple’s new MacBooks and MacBook Pros run Windows directly without an intervening “virtual machine” program like Parallels or Fusion?

Yes. All Apple Macs running the current Leopard operating system, including the new laptops, come with the ability to directly run Windows XP or Vista. Using Apple’s built-in “Boot Camp” feature, you can start up the computer in Windows, instead of the Mac’s own operating system, which turns the Mac into a pure Windows machine, with no trace of the Mac operating system running. The upsides of this approach are maximum Windows speed, and compatibility with the most graphics-intensive Windows programs, including games. Note that, to run Windows on a Mac, you must obtain and install a fresh, boxed, full version of XP or Vista. Apple doesn’t supply Windows.

I have a Yahoo email account, and wonder if Yahoo allows receipt and storage of email directly via a computer email program, such as Outlook, or is it all Web storage? Can you do both?

Yes. Yahoo offers a “Plus” option, for $20 a year, that permits users to receive and store their Yahoo email using a locally installed, instead of Web-based, email program. This approach does work with Microsoft Office, as well as many other local email programs. And you can still use Yahoo’s Web-based email interface at the same time. The Plus option also includes other benefits, including the elimination of ads and a doubling of the size limit on individual messages, to 20 megabytes.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

I read your recent column about running Windows on a Mac. Is there a way to run the Mac OS X operating system on a PC, like a Dell or a Sony?

Yes, but it is really only for tinkerers and hackers, and even then, it may not work fully or smoothly. Apple makes the process difficult, both technically and legally, because, unlike Microsoft, it is not in the business of selling its operating system for use on other companies’ hardware.

Therefore, I know of no simple software for average consumers that can install OS X on a non-Apple computer without any technical knowledge and with full assurance that the operating system will be completely compatible with the hardware. There is nothing on the market like the products that allow people to run Windows on a Mac.

A small number of techies do install Mac OS X on non-Apple PCs every day, and some people have created software to make this possible for people with plenty of technical knowledge. There is even a company called Efix that is selling a hardware module that it says will make this easier. Its maker warns the product is only for “enthusiasts” and it requires that you attach it to the computer’s internal circuitry. Also, it only works with certain types of personal-computer hardware.

One more thing: Apple takes the position that its licensing terms limit the use of OS X to Apple hardware, so, even if you can pull it off technically, there could be legal jeopardy involved. In fact, Apple is suing a company called Psystar that sells non-Apple PCs with OS X pre-installed.

I have a new PC that came with a 64-bit version of the Windows operating system. It gives me a choice between using a 32-bit Internet Explorer or a 64-bit Internet Explorer. Which should I use?

The 64-bit version of Windows, which is rarely used by average consumers, can make the computer faster, but only when running programs that have been written in special 64-bit versions. In the consumer arena, there are too few such programs, and thus too little benefit, to justify paying extra for 64-bit machines. In fact, most people who have computers running 64-bit Windows are mostly using older 32-bit programs, which run fine, but aren’t made quicker.

So, the 64-bit version of Internet Explorer may run faster. But there is a downside. Because of the relative rarity of 64-bit users, some browser add-ons and toolbars and some of the Web technologies that power the features of Web pages, aren’t compatible with the 64-bit version of IE. On top of that, you may not notice any huge speed difference as the perceived speed of Web browsers depends more on the speed of your Internet connection than anything else. So, for now, I would stick with the 32-bit version, for compatibility’s sake. You can always install the 64-bit version later, if you decide that the Web sites you frequent and the add-ons you use work well with it.

I am running a Mac with Windows XP Pro in Boot Camp, which requires rebooting to change operating systems. Is there some way I can use my already-installed Boot Camp setup as a virtual machine using VMWare Fusion, so I can run my Windows and Mac programs side by side?

Yes, there are two ways. First, Fusion allows you to treat the Boot Camp section of your hard disk, called a “partition” — which is essentially a separate Windows PC stored on your Mac — as if it were a “virtual machine.” This approach still allows you to reboot the entire Mac into Windows when you’d like to do so, in order to perform the few tasks that Fusion can’t handle, such as advanced 3D graphics.

The second approach is to simply import the Boot Camp installation and turn it into a purely virtual Windows computer, as with any virtual Windows machine you would create in Fusion. If that meets your needs, you can then actually remove your original Boot Camp Windows installation, which will likely free up some hard disk space. To do this, just select your Boot Camp partition, which Fusion automatically detects, and click on Import under the File menu.

You can find Mossberg’s Mailbox and my other columns online free at the All Things Digital Web site, http://walt.allthingsd.com.

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