Hey, how bad can it be?
You need drivers for:
* video
* network card
* modem
* sound card
* PCMCIA (possibly)
Finding and loading them sounds a lot easier than buggerising about with an over the top install on a system that is virtually certain to have all sorts of Compaq-specific crap loaded, and more than likely has the usual bucketload of spyware waiting to trip you up with something subtle.
The only thing that makes me worry is that it is a Compaq, and if there is one big-name company I don't trust to have ordinary standard basic device drivers on their website, it's Compaq. Often, they don't even give you drivers on CD, just a pox-ridden recovery CD. Or, even worse, an utterly shonky restore partition.
But, given that there are only two ways to do this and you have to take your chances one way or another, I guess you just have to choose your poison. Good luck!
Me, I'll take $10 on red.
(Actually, come to think of it, I'd upgrade them to the best of all Windows versions: 2000 SP4. I hate trying to make bloody XP (any flavour) talk to a network. Networking XP is poison, pure and simple.)