If you've never read a biography of Twain, this is an excellent introduction to his life. It covers all the high points and is replete with quotes, shots of living quarters, cities where he lived, and family photos, as well as a few shots and video clipes of Twain himself. The narration is pleasing; the voice acting for Twain is superb, and the audio commentary by Twain biographers is clear and helpful.
If you're already familiar with Twain's life story, the DVD is not going to reveal anything new to you, and you will likely find it frustratingly scant on details. You don't learn, for example, much about Twain's approach to writing, his inability to accurately estimate how popular his works would be, his continuing schemes for sequels, or much detail at all about the printing machine that bankrupted him. Instead, the DVD mostly follows the major points of his life - where he lived, what he published, family details.
The best bits for someone already familiar with Twain's life are the video clips interspersed throughout the DVD. It was a great joy for me to see Twain's famous shambling gate, as well as his cigar smoking.
In any case, highly recommended to anyone, novice or expert.