If you do not mind paying for a DVD authoring program, Nero (Nero Vision part) is actually pretty good.
Its pretty easy to get the hang of too, but also has alot of advanced settings should you decide to try it out.
ConvertX works pretty decent, but I was always disappointed in its video quality.
Things may have changed though, it has been well over a year since I tried it last. But thats just my opinion, many others disagree entirely.