If you are talking about videos downloaded from Limewire, then no way are they DVD. Also unless it's really old all those players will work (Windows XP)?

Windows Media Player isn't very good. You would be better off using those I mentioned above.

VLC should even play DVD

Video downloaded from Limewire is normally .avi , .mpeg or .mpg

DVD is .VOB

what is the last piece of the filename? (Don't mention whole titles)