I just made a DVD which is primarily a video slideshow with stills that I want to play at a reception.

I followed the instructions to for end action and set it to loop, but all it does is goes back to the menu. I want it to automatically start playing from the beginning.

I think I'm missing something pretty basic. If I want the loop to be the whole video, the video is 7:15 in length, wouldn't I put the duration at 7:15 and the loop point at 00:00? What am I missing?

I am using Sony Vegas 9 and DVD architect 5.0

Make it a single movie (File - New - Single Movie) instead of a menu-based DVD.
Set the End Action to itself and it'll loop until you press stop or eject it.

Chris, after changing the end action to "loop", you then must change the destination of the end action. It needs to be changed to point to itself.