Can't play videos in Win2k

I have a problem that I desperately need help solving. I
can't play back videos in Windows 2000 using any media
player except Quicktime. My CPU resources get used up
then the media player in question freezes. This happens
about 85% of the time. Any help is greatly appreciated.

OS: Windows 2000
Media Players Affected: Windows Media Player 9, Kazaa,
Divx Player 2.1
Video Card: nVidia GeForce2 Ultra
Driver Version: 4.4.0.3
Affected Media Types: MPEG, MPG, AVI, ASF