Bad media can readily cause that message to come up. I've tossed enough frisbees when running into brand new factory sealed containers with data on the blank media already. That was a little rare. But you can expect to toss a few on occasion if you burn cd-rs or dvd-rs on a regular basis. A bad disk doesn't point at a virus.
Smitfraudfix is tool used with some limits to see if some type of virus or trojan is to be found on a system. First try some different media to see if you got stuck with a bad batch. You can add protection by downloading free antivirus programs like the AVG 7.5 free edition by Grisoft, Ad-Aware, SE Personal, Spyware Terminator, Spybot Search + Destroy, free firewalls like Jetico and Comodo, etc. to keep things off as well as locate anything that gets onto your system.
