What I did was really simple. A friend of me said it was ridiculous to always update your drivers. So I installed the default drivers from the CD I gained with my videocard. After that I set AGP to 4x and Fast Write off (didn't work for me with the newest drivers) and yesterday and today I experienced 1 crash. The rest of the sessions lasted for 2 hours. Not freezed up but logged out myself.
I don't wanna call out succes just yet (that's calling misery upon yourself.) So this is all speculation and no confirmations. (I still wish for luck every time I start the game *prays*

.) I just HOPE it will last to work quite well as it did these two days.
Hope this can help some people with their freeze-ups.