If my camera records in 720P should I export the video in 720P or raw DV for best quality?

I have a camera that records in 720P and when I start a new iMovie project in iMovie HD it asks you what format you want to use. I can either use DV or 720P. Would DV give me the best resolution when I burn it to a disc, or should the resolution be the same as what the camera recorded it in?

This is urgent if anyone can please help me out.

Thank you