Yes in general the open source Nvidia driver for linux is very slow and underpowered compared the to the closed source driver provided by Nvidia. Most distros have a method of easily installing this driver. In Ubuntu just click System -> Administration-> Hardware Drivers and it should then scan your hardware and prompt you to activate the Nvidia proprietary driver if you have a supported card. If your distro does not have a system for installing the driver you can download it off of Nvidia’s website and install it manually, which is not hard. Nividia has made a fairly easy to use wizard for it but you’ll have to launch it from the command line.
Try and update the driver and get back to us with your results or issues.