I agree with caroline this sounds alot like a hardware error. Can you please attach a copy of your /boot/grub/menu.lst file and any hardware specs you know.
** Changed in: Ubuntu Status: Unconfirmed => Needs Info -- intermittent boot problems edgy https://launchpad.net/bugs/61337 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs