How do you adjust screen resolution in Ubuntu 10.10?

Just installed Ubuntu on a gateway desktop and I have it hooked up to a 56'' JVC HDTV...the outer edge of the ubuntu desktop is off the screen on all sides...I can still click on everything but can't see everything...if I go to systems and then monitor it only has 2 other resolution options and both of those are worse...any ideas? If adjusting the resolution is easier in 11.04 just tell me and i'll upgrade....thanks