I have recently been looking into creating a DVD movie in Ubuntu from an .avi file. After a lot of research and testing a few methods I have found one that I am extremely happy with. This method involves using Tovid which is a collection of GPL video disc authoring tools according to the Tovid site.
For this example/tutorial I am going to be using Elephants Dream, a open source movie made exclusively with open source programs and tools. I decided to use the .avi version as I wanted to make a .avi file into a DVD although Tovid can handle most video files.