After updating to Ubuntu 11.04, the screen resolution got messed up. It refused to recognize the native resolution of 1280×1024, but instead just used 1024×768. What’s the point of having a nice large monitor if the OS can’t recognize it?
I first tried editing the xorg.conf file, using the instructions at metafilter.
That didn’t work, but a few other posts suggested installing the VBoxAdditions. I thought I had already done so, but reinstalled it again to be sure. Sure enough, after the restart, the screen showed up at the full resolution.
Another problem was that the ugly root theme kept showing, no matter what I did. Although it seems a bit dangerous, I finally tried creating some symbolic links to get the root theme to look the same as what I want to use. Instructions are on tombuntu.com