I myself am an inveterate Mac Head...but I have had some experience with Windows machines and my brother is a software engineer who has kept many Windows based machines running long after their time had come. The Windows machines that he has shown me that have been kept going have been what he calls "Frankensteined"...they've had so much stuff replaced inside of them that "Frankenstein" has become the verb for the process. Even my brother has finally surrendered to the idea that you just have to buy new every few years with Windows machines...it just becomes non-cost effective to keep switching in new components.

It seems like every time Windows is upgraded its operating speed flies on the newest machines but the older machines slow down. As PB and Canuck have suggested you might be able to get away with what Mac folks call a "clean install" of the operating system (don't know if there's a corresponding Windows term).

Macs do tend to last longer (years) with no hardware upgrades...it seems like it's financially crippling to even DO a hardware upgrade on a Mac...but there's the issue of initial cost and the recent trend toward Mac introducing a new operating system every year at about $100 a pop. Not that you have to upgrade every time...I have Macs here running several of the previous incarnations of OS X and one that still runs OS 9 and they all still perform well.

That aside, if you know Windows, it's probably to your advantage to stick with it...I expect that it all evens out in the end...and some of the package deals that I've seen on new systems look like great values. Don't know if you've gotten into the whole audio/video aspect of the computer world but they're now more like computer/stereo/dvd player/lcd TV systems and it's nice to snuggle up to the ol' computer and watch "Blade Runner" or "Room Service" once in a while. A new system with a decent size monitor is a pretty good investment these days.

Best

AA