Computer Crash/Freeze

Hello everyone.

I've had my computer for some time now and it worked nicely with everything until I installed some new Nvidia drivers.
I'm pretty sure that the new drivers is to blame but anyway here's what happens.

In games like Team Fortress 2 and Left 4 Dead it can suddenly crash and freeze, making no option you usually do usable. CTRL-ALT-DEL doesn't work since it's completly frozen. All that works is the reboot switch.

This is getting on my nerves since my computer didn't have this problem before. I have no idea of the old version of drivers I used to have that worked fine but it seems to me that every new driver Nvidia releases is just crap! Always freezes.

This is my specs:

Win Xp 32-bit
Intel Core 2 Duo E6550
2gb ram
160 GB velociraptor disc
500 GB disc
Leadtek Winfast 8600 GTS 640mb.

if anyone have any idea on what to do against this problem please help me.

I've tried pretty much this sofar:

Antivirus check
spyware check
scandisk
defrag
uninstall - reinstall drivers.

at first I though it might have been a heat problem but it's around 50 degrees and up to 60 degrees while TF2 is on.
anyway dunno what to do but you might help me.

Best Regards

Silvah