I jsut started using this program and downloaded two files that will not play in Windows media player 10. Does that mean they are corrupt?

Possibly! Stay away from T3 sources for downlding from.

See: T3 Spammers & make a note about how you should always check the File Size Versus the Bit-Rate.

A couple of people have suggested fixes to those so called corrupt files. There's apparently at least 2 utility apps out there that can fix many. I don't know about all. See these: 1. video-fixer & 2. MP3RepairTool

Tell us how well they work!?