Fedora Core 8, Nvidia, Compiz does not work (SOLVED)
Two times I've run into a situation where Compiz doesn't work with the nvida driver. Symptoms: after clicking "Enable desktop effects" there are no window decorations.
Also, when logging in as another user, it just works.
The solution is "gconftool-2 --recursive-unset /apps/compiz", found in another thread here.
And I forgot it the second time I ran into this - time to document :-)