Games won't stay in fullscreen

I just installed unreal tournament 2004 and when I set it to my monitor's recommended resolution it starts jumping in and out of full screen until I turn it down.

In addition to that while I was playing the game suddenly jumped into windowed mode and my mouse stopped working, at which point I had to manually shut down. This actually happened to me once before in open arena.

I have an NVIDIA GeForce 8800 GT video card and Ubuntu 8.04 64-bit, does anyone have any idea what's going on?

Disable Compiz.

metacity --replace

if it works. Install fusion-icon from synaptic Package Manager to switch it on/off.

Install compiz-switch and use it when you play games.:KS