No computer that was returned from ANY customer should EVER be resold (or the hard drive thereof) with whatever data that customer left on it. There could be many bad things on there, including viruses, trojans, kiddie porn, and communication gateways for terrorists (yeah, gotta toss in the T-word somewhere).
This means wipe the disk completely and re-image the original OEM operating system in its initial state (ready to ask for your name and such).
Newegg appears...
