thanks for the kind replies guys, and thanks Armistead, that's a good tip on the game shortcut, i didn't know about the gu.exe stuff.
the computer is powerful enough i know that 3.7ghz of quad core with plenty (8GB) of ram. i know it's not the computer, because i transfered the saves to another machine in the living room with a fresh install and it crashed exactly the same way. the drivers are all up to date.
i will try to delete old saves from time to time like you suggested, i think that's a good way to keep things fresh and lean.
any other suggestions would be appreciated