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.

Last week, when you wrote about the ChaCha cellphone search service, you didn’t say how they make money. Are they collecting phone numbers from customers so they can send spam text messages, or sell the numbers to others who will do so?

ChaCha allows you to ask any Web-searchable question, by speaking it or texting it over a mobile phone, and then it sends you the answer via text message. The company charges consumers nothing, but says it is hoping to make money by striking deals with cellphone carriers to incorporate the ChaCha service into their current 411 phone-number look-up services. Also, it hopes to eventually include ads in the text message answers it provides.

In addition to the message that includes the answer, ChaCha sends you a message saying it is working on your request and restating your question, so you can see if it understood you correctly. It also sends an introductory text message to first-time users and occasional tips on how to use the service. Scott Jones, ChaCha’s chief executive, asserts that “we do not spam” and “we never make phone numbers and/or email addresses available to others.” He said the company is updating its privacy policy to make that clearer.

We have DSL service. I use several Web-based applications, one of which is online backup, and my husband is concerned that they degrade his use of the Web, which includes creating Web sites. I contend that that is like saying turning on one light bulb is using too much electricity, that two people on one DSL line aren’t using up too much bandwidth. Who is right?

Every situation differs, depending on exactly which programs you are each using, how you have them set, whether you are using them simultaneously, and how fast your DSL connection is. However, in general, your husband is correct that it is possible for heavy Internet usage on one computer in a home to slow down Internet speeds on another.

This is especially true with something like online backup, because it relies on your DSL account’s upload speed, which is typically far slower than the download speed. If your online backup program is trying to push a bunch of files over a slow upload connection, while he is in another room trying to upload new versions of a Web site over the same narrow upload pipe, it could affect the speeds he gets. You might try coordinating or staggering those online activities that involve heavy uploading. Normal Web surfing or emailing shouldn’t require any such coordination.

I am thinking about purchasing a Dell (DELL) XPS One all-in-one desktop, but I have one question. Does the Dell’s built-in TV tuner require any extra attachments to watch TV right out of the box?

You can watch over-the-air stations and analog basic cable stations right out of the box, without added equipment. However, you may want to connect a small desktop antenna to improve reception, which is what I did when I tested this machine. To use the XPS One with digital or premium cable or satellite stations, you would have to connect it to a cable or satellite receiver, just as most people do with their TV sets. This requires the use of an adapter that comes with the machine.

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