From my experience the video should be in a mpeg2, wmv or avi format.
The other thing is that you have to make sure you have the proper codec on the other computer to play the video.
For example if you have an AVI video with a H.264 codec and you are able to play it on your computer. When you transfer it to the other comuter you have to make sure it has the H.264 codec.
I hope this helps