[ubuntu] Strange problem at "Installation Type" screen (12.04.2)

view story

http://ubuntuforums.org – Trying to install ubuntu desktop from bootable CD, and the installer hangs at the screen which asks what installation type: Alongside current OS, replace current OS, or create custom partition table. I would like to create my own partition table. But here's the problem. It doesn't just freeze completely and allow me to do nothing, but what happens is that clicking "Continue" does nothing. Almost as if the button is disabled. The "Back" and "Exit" buttons work fine, just not "Continue", no matter what option I choose. (Hardware)