Not sure if this is the right one, but the song "back to reality" was by Soul 2 Soul released in the early 90's is that the one?? will keep my eyes peeled for it
It's "Going Back To My Roots". I don't know if it's the original Odyssey version or a cover (all the trailer features is the piano riff, so it might have been covered specially).
That particular version of Going Back to My Roots with that piano riff can be found on the versions by FPI Project and Richie Heavens, which use the odyssey chorus but add new lyrics. e.g
"I've been living in a world of fantasy
And I'm going back, going back to reality"