What he's saying is that you make it a slave, scan it real good with virus scanners, and copy the files over. As for me: I would format the drive after copying all needed files over to make sure no viruses can affect your computer. It should be pretty safe, so long as you don't activate any files on the drive until you scanned them.
Actually, depending on your scanner, you may be able to just scan the files you need. If they're clean, copy 'em over. Then format what's left to prevent virus spreading. But to be on the safe side, I'd scan my C: drive afterwards for viruses, just in case they do spread. You can never be too careful.