Installed Ubuntu 11.04, downloaded updates, and now it won't boot
I installed Ubuntu 11.04 from an .iso created CD. It loaded up and worked fine on an older PC. Then I downloaded and installed the latest updates via the "update manager", and now the system boots to a grub prompt and claims that it cannot find the operating system and asks for a "boot floppy" (that of course I don't have). I hit <tab> and got a whole list of commands, but none of them mean anything to me. I was able to boot from the startup CD, but doesn't help me at all - the only choices it offers is to "install" or "run from the CD". I am at a complete loss.