What I did was while the game was loading I took a Flash Card that looked old, and plug it into the computer and unplug it fast. The game still crashed.
This proves the theory that any programs/apps that starts running in the background, while the game is running, will suddenly cause the game to crash.
It is also possible for MSN and some messenging programs that can crash you, like when you are playing and someone sends you a message.
Also, I notice I can't Alt-Tab Stalker CS in fullscreen, and one part of the error logs reads: "Access Violation" of some sorts, which can mean that the program doesn't allow any sudden stuff to occur. It could be a hidden starforce or protection setting in the game itself.
OS: Vista Home Premium RAM: 3GB CPU: 2.60 x 2 AMD Athlon D.C. 5000+ Nvidia Geforce 6150 SE (Yes I know the card sucks... It comes with it 1 year ago for $700s in Canada)
EDIT: This is a bit of a joke, but apparently my brother picked up this compact card on the ground somewhere and it still had photos in it... Just weird ones with weird poses (I shouldn't say).