Last fall, I advised average consumers with aging PCs to hang on until new Vista PCs emerged, rather than trying to upgrade existing models. I still believe that was the right course, because Windows upgrades are so tricky. But it turns out that even new Vista PCs have two big downsides.
First, Vista isn't all that exciting a replacement for Windows XP. It's much prettier and has much better searching, and Microsoft claims it has much stronger security, although you still need add-on security software.
Second, to an extent that amazes me, makers of Windows software and hardware have failed to update their products to work smoothly, or to work at all, with Vista. In my house, for example, the only built-in Vista printer driver I can find for my printer doesn't allow the two-sided printing I can do with Windows XP and Apple Macintosh computers.
So, if you desperately need a new Windows PC, be prepared to be underwhelmed and to be frustrated by incompatible software and hardware. And if you're not desperate, you might wait another six months or so for the software and hardware to catch up -- and for Microsoft to issue some bug fixes.
Or you could buy a Mac instead. I still believe the best desktop computer on the market for mainstream, nontechnical consumers is the Apple iMac. It has gorgeous hardware and superior built-in software. Its operating system, Mac OS X, includes most of the key new features of Vista. And the iMac can even run Vista, along with its own operating system, if you need the occasional Windows program.
Apple has delayed until October the release of its new operating-system version, Leopard. But it's almost certain that any Mac you buy now will upgrade to it smoothly. (See my Mossberg's Mailbox for more details.) And the Mac is still largely free of the security problems that add such hassles to using a Windows PC.