BAD RELIGION!
Supersonic by BAD RELIGION (the best band ever) and the first piece of music you had was from the Halo 2 soundtrack which is fantastic (You might've mentioned them in the "Audio" info though ;) Unless you just didn't have space)... Music gets a 10 just for those (Despite you having the god-awful Sonic Heroes theme in there).
The graphics were great! Super smooth framerate and speed, good animation on the facial expressions and lip-synching, really nicely done. There was a good semi-3D style to them too.
Good style used throughout. Nice menu with good transitions to other parts which also gave a lot of interactivity and there was a lot of information to read for those interested.
As for the whole movie it seems like it would've been great if you managed to finish it and show us how the story developed.
I myself used to be a huge Sonic fan right from the original 2D games on the Mega-Drive until the games went downhill (after Sonic Adventure 1, which was good. SA2 was ok, but SH was absolute crap, imho. This "Shadow The Hedgehog" game looks like the worst thing ever... now I'm ranting, lol), anyway...
I can see a lot of hard work went into this movie! Graphics, animations, sound synching, style, extras, a lot of stuff, I'm amazed at the size your .fla got to. I thought the one I was working on was big (at 114MB)!
Anyway, good work! Keep it up!