Comment 14 for bug 137401

Problems running Compiz are unrelated to this bug. An all-white screen when running Compiz under Xgl generally indicates that you've manually installed the nvidia drivers from nvidia.com, and they've overwritten some important libraries without backing them up. Reinstalling all the various mesa libraries (you can search for them in Synaptic) and then installing one of the Ubuntu-packaged nvidia drivers (from the Restricted Manager, for example) should fix that.