I would try encoding them to quicktime. It is much more supported that MPEG4 and is also highly supported by Macs. MPEG 4 doesn't come standard on Windows machines unless you upgrade you windows media player to version 9. I would recommend Quicktime or even Windows Media Player or Realplayer should be good. The quality should be pretty good and you shouldn't have any trouble being able to play the video on any computer. Good luck!