See my thread at
and what i did: I added Option "UseCompositeWrapper" "true"
to the device section in xorg.conf. This works with the 169.xx and newer generation of drivers. And turn Compiz on again. Please let the forum and me know if this has helped!
If this option fixes these issues, I hope the forum moderators will put it finally in their FAQ to use this option in the case of crashes.