Recording Xbox 360 gameplay?

I want to record a demonstration of some gameplay on an Xbox 360. As far as I can tell there are no copywright issues with this. However, although when I connect my Xbox 360 to my DVD recorder, the signal that gets to the TV is fine, the actual recording has the image 3 times in horizonal rows. Does anybody know what causes this, and anything I can do to fix it? The connection is via SCART.

You need a capture card, either in your computer or externally. http://www.gametrailers.com/player/usermovies/59014.html?id=59014