USB Gamepad

[Lluminari]

Hey there, first time poster.
I'm running XP Home SP3, all the latest drivers, new DirectX...the works. Everything is up to date.
The other day I go to play Prince of Persia on my gamepad, and the sucker doesn't work anymore. I have no idea why. I try a lot of things from uninstalling the driver to try and go to it's properties. The thing works on my room-mate's computer just fine.
Could it have been a download from MSN that did it? I don't know.
I've read other forums that have had similar problems...back in 2004. Does someone know of a way around this?
I've tried my other USB ports, my power is fine...my PC is custom built and the power runs at 650W. So it can't be that. All of my other USB stuff works, ext hard drives, cam, wireless keyboard and mouse.
When I DO try and get into the game controller properties it just closes itself? Which is weird.
I've done everything under the sun but reinstall xp. Even checked out the services.msc...it's fine.
My gamepad is a typical looking ps2 gamepad with rumble support. There's nothing wrong with it. Device Manager says nothing is out of the ordinary...my pc is just acting like it's not there. I tried it on other games to no avail.
I'm a smart fella and this is weird.

Any help would be wonderful.