The system hangs randomly, no matter what I do. Sometimes I can use the system fot an hour without the system hanging, but mostly it hangs within a few minutes after booting. I used the uninstall command you gave me. Everything seems to be back to normal again. I have no 3d support, but atleast the system is running again. I'll have to spend some more time learning about Linux before I'll install the Nvidia drivers again.
Thanks for your help!