|use a knoppix cd|
keep the drive in the original system and detected/seen by the bios. boot the knoppix cd and see if you can see the drive contents
doesn't sound like a virus to me but a platter/disk failure. You will know more when you try to access it via knoppix
The hope is you see folders and files. Otherwise you can have partition corruptions or physical failure of the drive.
Sure makes backups a great idea now doesn't it?