Why won't my desktop work in ?

I just started using Linux, specifically Ubuntu. I get the loading screen fine, and the text based beginning fine. However when it goes to the desktop it flips out on me and it seems like every line of my screen is shaking so the images are disociating. And it's not just Ubuntu. I've also tried Fedora and openSUSE. They all do the same thing. What is wrong and how do I fix it?