It really doesn't take much for me.
UP- the scrapbook scene. The beginning makes me sad but I don't cry but that scrapbook scene, god that was brilliant writing.
Wall-E- Excellent ending
The Railway Children- I cried out of happiness when they were reunited with their dad.
LOST- The end of Season 3 and 5, when Charlie dies and so does Juliet. Season 6 ruined the latter's final moments.
There's more, I just can't remember.
Oh yeah, Scrubs, My Lunch. The one where "How to Save a life" is played. And where JD gets off with Molly, the subplot with Dr Cox is fantastic. Always gets me. As it's a subplot you'll only know them for 10 minutes.