Grub Problem

I let a student use one of the lab machines to play with virtualbox, and then it stopped working with a grub error. So, I booted up with PuppyLinux and then try to rerun grub-install. It failed though and I think wiped out a bunch of files on the disk. It is unclear why, but about 1 Gig out of 8 is missing after I rebooted. Since it is close to the release of 9.10, I'm going to wait and try installing that to see if there are performance differences, but I wanted to make a note of this strange behavior.