I think mine has to be The Commitments. I love that Irish humour, plus there's some brilliant music and a killer script. I lvoe the bit where the main guy is going to go up in the lift to see one of the girls in her block of flats, and there's a young lad standing by the lifts with a horse. The guy says to the lad, "You'll not be taking him up in the lift?" and the young lad says, "Course I am, mister, the stairs'll kill 'im!"
But close contenders were:
This Is Spinal Tap
Crossroads
The Blues Brothers
Still Crazy
Almost Famous
If we get a few nominations we can have a poll