I use an Nvidia card in Linux and it works great. I am not sure what happened
when you say it killed the system. Likely you ran into an xorg.conf problem. You
should be able to 3D graphics if the card supports it. Reasons not to get 3D
might include the wrong video card driver is used, the configuration is wrong,
you have not installed the 3D desktop effects files, or the monitor is set to
too low a resolution.

Make sure that Ubuntu has installed the right driver. You can get Nvidia drivers
from Nvidia or use the ones in the repositories. With my card an icon that looks
like a computer card appears in the system tray and it says that there is a
restricted driver available. I put a check in the box and it installs the
driver. You can find the same thing in System| Administration| Hardware Drivers.
Once installed I had to reboot to take advantage of the change. Check that your
monitor is properly configured, too. You can check the settings in System|
Preferences| Screen Resolution.Then to take advantage of them install Compiz
Fusion with its libraries plus Fusion-Icon. Let us know how you do. You should
see GL Desktop appear in the System| Preferences menu. Otherwise look for Compiz
Fusion Icon in Applications| System Tools.