XP on partition - games minimize randomly

I've tried basically everything I could find but my games on XP (on Bootcamp) keep minimizing randomly, its sooo annoying.
I did an XP Repair, ran a AVG spyware sweep and found nothing, uninstalled AVG, and I basically uninstalled everything else I had except my games and nothing has worked.

Before my games were working fine (I had like Bioshock, Mirrors Edge, COD5), then I went to my friends house and installed Steam. Somewhere in there this problem started occurring and so I tried uninstalling it, still no luck.

I also notice my taskbar/desktop steals my windows' focus such as Firefox, then my cursor has the arrow+hourglass for like 2 seconds. I highly doubt it's spyware but I need some advice.

my Macbook Pro is 13", 2.53MHz, 4G RAM, nVidia 9400M

pleasepleaseplease helpp! :[[