Full Screen Problem In Ubuntu

I'm running Parallels Desktop 4.0 for Mac, build 4.0.3846 on a 17" MacBook Pro running Snow Leopard. When I run Ubuntu, it comes up in a small window that's a little larger than 1/4 of the entire 17" screen. If I expand the window, the window gets larger, but all it does is put a large black background around the same small Ubuntu desktop. What I expect it to do is enlarge the Ubuntu desktop to fill the entire window. I know that this is some kind of bug, because I also have a Windows XP Pro SP3 virtual machine, and it works exactly like I expect it to. Can anyone please help me resolve this issue? It's extremely important, as Ubuntu is completely useless to me in that small of a window. Just a note, I installed Parallels Tools for Ubuntu today and the installation seemed to work perfectly. Please help!

 

Please help!!!!

HEY ADMINISTRATORS!!!!!

When I will receive an answer for this question?

 

Do you morons even bother reading these freaking posts! Support, what a freaking joke!