I've got the same error, and I'm a noob too. So my situation is I had debian 4.0 up and running for a while, and i installed virtual box - because I cant do everything in Linux - yet
anyway after i installed VirtualBox , i granted my user acces to the vboxgroup [sp?] after which i learned i had to log out of that account to for the grant to take place. When i logged back in i got a "failed to initialize gdm" error , so i said igore and the screnn "froze" I then rebooted the machine and I'm getting the grup 22 error.
I do have Knoppix live up and running if that helps, i checked gparted and it only shows 1 partition,where i had 3 before ( 2 ext3, one swap)
Thanks for any help.