Ok, was offline for a long time and forgot to check in on this topic...

Quote Originally Posted by Niku-Sama View Post
you should be able to get away with MechWarrior 3 and expansions on that hardware in xp.

but yeesh ti4200?
What's wrong with the ti4200? It had good recommendations on places like Vogons (and I was told at the time that it was the best that would work in both 98SE and XP, though I've now heard contradicting info but the later cards that apparently still work are only slight improvements).

Quote Originally Posted by Nz17 View Post
First of all, yes, yes you should install and play Quake III Arena. It is excellent, and people still play it online frequently even today.

Second, I still run Windows XP on my main computer, and even "modern" games like the completely-up-to-date 2018 release of Team Fortress 2 runs just fine on WinXP. It is surprising how many new and recent games will run on XP even if they don't claim as such.

Third, search GOG.com if you want good DRM-free games that will run on Windows XP. Some of them won't, but they will state as such in their requirements and those are rare.

Fourth, are you principally interested in physical copies of the games (CD's / DVD's) or downloads? Knowing which will make recommendations simpler.
That last one is tricky as I've played a lot of downloaded games, usually freeware and GOG purchases. Was an excellent puzzle game called Hex-a-Hop that I was hooked on for a bit.

But for the sake of narrowing it down let's say "commercial games that had a physical release back in the day."

Altho I also found that the fangame Mega Man Unlimited runs just fine on this doohickey, and using a Playstation-to-USB controller makes playing it indistinguishable from playing a console Megaman game...