Also, "Don't Stop Me Now" from Shaun of the Dead. http://www.collegeslackers.com/video/shaun_of_the_dead
Don't tell me we haven't mentioned The Godfather theme? The Good, The Bad, and the Ugly: The O Brother, Where Art Thou? soundtrack is awesome. Spoiler Freakin' The Nightmare Before Christmas: Spoiler My roommate randomly bursts into this when he's in a good mood, complete with gestures. But Superfly is the best soundtrack ever made: Spoiler (skip to about 1:50)
That reminds me of a really good song from one of the best blacksploitation films of the 70s, written and sung by James Brown;
There are so many movies or TV shows that I immediately identify with a song: Sopranos Theme song True Blood intro Reservoir Dogs - Stuck in the middle with you The Commitments - Mustang Sally 9.5 weeks - You can leave your hat on Animal House - Shout The Breakfast Club - Don't you forget about me Risky Business - Old time rock and roll Against all odds - Take a a look at me now
And how could I forget: Wayne's World -- Bohemian Rhapsody And the all-time best use of FreeBird ever. The Devil's Rejects ending in all of it's Sid Haigish glory: