Quickcam, Media Player, games, problems

I have an HP Pavillion PC 333 mhz, 64 mb RAM, 30 gb hard drive. Things were working fine until I loaded a Logitech USB Quickcam. After installing the software for it, it worked fine and so did everything else on my pc. However, after rebooting, the Windows Media Player doesnt start (it just hangs on “opening”), online games that I have such as Counter Strike, Age of Empires, etc hang halfway into the loading process. The sound for the Quickcam doesnt work. Sound works for other applications however. I have tried uninstalling the camera, Windows Media Player and nothing can resolve the problem. Does anyone have any ideas? The scanreg /restore utility won’t work (it said “registry restore unsuccessful”).