This is as much a historical document as the life story of an iconic songwriter and activist. If you are looking for film of Woody singing, then there is a lot of footage included, but you really have to see this film as the telling of his life story. As such it is more a chronological documentary than anything else. His songs are consistently and very well placed within both the historical context of life and events in America at that time, and the relationship between Woody, his songs, events in America and the world, his family and folks around him is also made very clear.
This is a fascinating film and is added-to enormously by Billy Bragg's comments and commentary. The only other films of this type that I can think of which are of comparable excellence are the music documentary films by Martin Scorcese.
If you're a fan of Woody Guthrie or have an interest in the development of modern folk music in America, then this DVD is essential viewing.