I have a Canon XL-2 I use to shoot live theatre and edit in iMovie HD. I usually set it to 24fps and 16:9. When I create a new iMovie project it used to be in DV widescreen but I'm trying out HDV 720p. However when I burn it to a DVD with iDVD the finished product tends to look pretty grainy full screen on a PC or on a high-end TV. Is this a compression problem and is there a better way to export to iDVD?