I was pretty excited about the release of Linux Mint 9, so I got an ISO, and installed it next to my Ubuntu and Windows XP. Installation went fine, until I restarted my machine. When I boot, right after the memory count I see the following:

Verifying DMI Pool Data.......
Boot from Atapi CD-ROM
error: unknown filesystem.
grub rescue> (cursor blinks)

Whereas I'm still excited about Mint, I must get back to Ubuntu. How do I put things back? Please help!!