There's one more option, temporary I hope, use Wuby. Go here
and scroll down, download and run wubi.exe.
What about your PC? How old is it? Post some specifications. Find info about your BIOS so that you know what "Removable" means, it should be F2 or F12 or alike during start up or look online.
As alraedy said, post the might be errors during boot time. Btw, how long did you wait for Ubuntu to boot? I've recently been installing 10.10 on my brother's PC and it did take some time before that purple boot screen with 5 dots has gone away.