Try VLC PLAYER since it usually can decode it and play better than Windows Media Player.
However, if you turn it into a Video DVD you usually find the quality is reduced to SD or 480i or 480p.
I am having trouble burning my own movie files onto a dvd-r so that another computer can read them. The movie files have been recorded in HD on my own camera and uploaded to Iphoto. I copied them to a dvd from there but for some reason when playing the dvd back on another computer (a pc) the movies dont play correctly. They skip and freeze. I just need to get these movies onto a dvd so another computer can download them and edit them on their computer. Help please!