Audio/Video help
 

When I play certain video formats (.avi, .wmv, .mpg) with Video Lan Client, and play The Sims 3 and other games my computer locks up hard. My video and audio drivers are up to date. I try older versions of the program and it does the same thing. I THINK it may have something to do with hi-def sound, but I’m not entirely sure. My sound is coming off of my motherboard.
I don’t like Windows Media Player. I can use it, but I prefer VLC because it plays every known audio/video extention.

What can I do to stop these lock ups?

My system specs are:

Biostar MCP6P M2+motherboard (using onboard sound), AMD 7550 Duo Core 2.51 GhZ CPU, 4 GB DDR2 RAM , NVidia GEForce 9500 with 1GB of onboard DDR, Realtek High Def Audio, NVidia sound drivers, 320 GB SATA hard drive... Windows XP Home SP3