What to do with a hand-me-down

I was given a Gateway FX530. It has, it seems, a bad video card, and that works intermittently. It runs XP (I know), but seems to be a pretty good machine, otherwise, with KB, trackball, monitor, speakers, etc. This was originally a gaming machine (2006??). I'm wondering if I could use the HD in my much newer eMachine, which is biting the dust, or if I could upgrade to Win7 and a new video board and run this one. It seems such a waste, to not be able to use it. It apparently has some unusual hardware.

Thanks!
Gran