I solved this problem myself...I removed a piece of video from the movie, and the DVD burmed correctly.  There was a clip of music in the film which I had made by detaching it from a piece of video, i.e., I filmed a scene, put it into the editor, then removed the video portion of the clip, leaving only the audio part.  This gave me some error message, even while still in edit mode.  The error message said to save the project and shut down the program.  After removing the offending audio-only clip, the movie burned correctly to a DVD.