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Tear Jerker: The Nightmare Before Christmas
The part following Jack being shot down, where we see all the kids crying as the police announce that they've yet to find the actual Santa Claus and Christmas will most likely be cancelled.
Jack's song after he's been shot down and landed in the graveyard... until he decides to fix things and not mope around feeling sorry for himself, realizing that his holiday is Halloween, not Christmas, and that even though he failed he did his best and he's ready to give his all for the next Halloween.
"Sally's Song" segment.
"Jack's Lament." One can really sympathize with Jack's boredom that's begun to turn into despair.