The soundtrack of "Guardians of the Galaxy" is one of my favorites in a long time, and the 2-Disc Deluxe Version is the one the buy.
DISC 1 - Awesome Mix Vol. 1
Disc One is the songs from the movie. All but one of them are featured in the film ("Spirit in the Sky" is not in the movie, although it was used in one of the trailers). Not only is the music good, but as you know if you've seen the film, the mixtape serves a significant narrative purpose. The songs here are presented as much more than just background music - these songs are important to the main character. My understanding is that the director even played the songs on set to help the cast understand the tone he was going for.
 Hooked on a Feeling
 Spirit in the Sky
 Come and Get Your Love
 Ain't No Mountain High Enough
DISC 2 - Original Score by Tyler Bates
The original score for the film is certainly overshadowed by the songs in the movie. But Tyler Bates is very a talented composer, and he delivers an emotional underscore here that serves the story well. It's not as compelling to listen to on it's own as disc one of this album, but there are some interesting tracks that I've found myself revisiting.
 The Ballad of the Nova Corps.
 Groot Cocoon
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