That's a huge question.
I have these soundtracks I listen to sometimes when I'm writing or as a prep before writing to help transport me quickly back into that world within the story. A lot of people I know have soundtracks for their lives, just like the commercial says. Some songs are so intensely popular that they're used in multiple movies, or sometimes aren't in the movies themselves but are in the trailers. "Ordinary World" is a hugely popular example.
But a bunch of favorite songs is not what a non-fic DVD needs. I'm sure the producer will take our ideas (or leave them) and come up with something practical. As someone who occasionally does creative stuff for other people, I understand the blessing that is a launching point.
I'm so, so curious about the entire DVD but now I'm especially curious about how music fits in. Music can turn a perfectly good instructional DVD and make it corny or unlisten-able. One of my favorite workout videos has such boring, awful music that I turn it way down and listen to my own techno and pop mix instead. There's a lot of pressure placed on the background that we don't think about. Music covers white noise, microphone crackle, and turns those dramatic pauses into, well, drama as opposed to someone standing around while the lights hum.
Which actually all plays into writing (as all things do.) Description is often background. When it's just a dry list of things present in the room and people gesturing, it's substance without the music. Description needs flavor, life, action. Think about it. Why were Tolkien's settings so rich? Because they were alive. They had music.
I'm going to go write some music now, while I eagerly await the DVD rough cut, coming soon (I hope) to a tv near me.