I can't believe no one has mentioned "Always Look on the Bright Side of Life" from Life of Brian yet.
For non-film music:
"I'd Rather Be Dead (Than Wet My Bed)" by Harry Nilsson "I Shall Be Released" by Bob Dylan (though I'd probably go with The Band's version) "When I Get to the Border" by Richard Thompson "Who Knows Where the Time Goes" by Sandy Denny "Meet on the Ledge" by Fairport Convention
I am a optimist- Knocking on heaven's door- Off to heaven I go , Theme from Highway to heaven and when I am in heaven I will be happy. Actually thinking about the next existence makes me happy, so no troubles on my side of life.
Remembering, remembering is like dying a little bit now you know it because everything comes around even if you don't want to and forgetting, and forgetting is harder now you know it is harder if you want to start over remembering, remembering, like a dive into the sea remembering, remembering what must be erased and forgetting, and forgetting, is how you lose dear things and [by] forgetting, and [by] forgetting, rare joys will end and forgetting, and forgetting, is how you lose dear things.