Dont know about the DVD as I only have the book, which comes with two cd's. The book contains sheet music for some songs. The cd's have sections of songs played by well known bassists. The great thing about these cd's IMO, is that you can completely isolate the bass, thus hearing the lines clearly.
AFAIK, the DVD is a general documentary type film, while the book deals more specifically with the bass and Jamerson.
In an "either or" situation, I'd say get the book, though the ideal thing would be to have both.
Hope this is of some help.