This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / The Princess and the Frog
The film really cranks up the waterworks with Ray's death. No, not Disney Death. Actual, factual, honest-to-God-death. But never fear! Just as you're sobbing yourself ragged, the happy tears chime in. Ray and Evangeline, together forever in the night sky...
Harsher in Hindsight moment, realizing that the cute moment where Ray bids his relatives goodbye is also the last time they'll ever see him... alive.
Tiana's ten-second reprise of "Almost There", when it looks as if the dream she has spent most of her life working toward has been anticlimactically shot down. It's arguably one of the movie's highlights.
That little scene where Facilier makes an illusory version of Tiana's dream appear for her. And the bit where Tiana, feeling betrayed and upset, lashes out at Ray by telling him Evangeline is only a star. And in a moment of Fridge Logic tear-jerkeriness in regards to Louis— that rather than trying to be a "normal" human to pursue his dream, in the end he just had to find people who didn't care about being an alligator.
Dr. Facilier's speech about Tiana's father; how hard he worked, how tired he was, and how he tried to hide this all from Tiana. It's even more tear jerking when you consider that he died during World War I before he could he even accomplish his own dreams.
Ironically it's this scene above all else that convinces Tiana that there's more to her dream than just business success. Her father never lived to see the dream they had been fighting for for so long, a silly little dream which "never got off the back porch", but that he still had the most important thing of all: his family.
Tiana: My daddy never did get what he wanted... But he had what he needed. He had love.
Despite having been prince-obsessed the entire movie, Charlotte instantly puts it on hold when she sees that Naveen and Tiana love each other, and offers the magic kiss with no strings attached so they can be human and happy together. And then it doesn't work, because midnight's passed and she's no longer the Mardi Gras princess. Just that quiet, "Oh, honey. I'm so sorry." as she sets Naveen down, knowing there's nothing she can do to help her best friend at all, is crushing.
A heartbroken Tiana telling Ray that Evangeline is "just a star" and that wishes don't really come true, driving the poor bug to tears as Tiana leaves in despair.
But it's something else of a good tear-jerker afterwards, and a minor Crowning Moment of Heartwarming. Despite being snapped at and told that Evangeline is "just" a star and can't love him back...Ray doesn't believe that. He's in tears, yes, but as Tiana hops off he turns to look up at Evangeline, and says "She don't mean that. She's just speakin' outta broken heart, that's all." Then he sniffs, pulls himself back together, and determinedly adds "C'mon, Evangline. We gotta show chere the truth!" He refuses to let someone tell him his feelings are wrong. And that's really amazing.
It's strangely touching when Naveen admits that he's had a wonderful, spoiled life where he was waiting on hand and foot, and then sadly admits that "I don't know how to do anything." It's like he's realised that he finally wants to be independent but... he doesn't know how.
The movie itself. Just... a good, traditionally animated, fairy-tale-ish Disney movie. It's like being a little kid again. It was just like going to see a movie at the cinema for the first time. Sometimes it's nice to feel like a little kid again.
Not that he didn't deserve it, but Dr Facilier's fate is quite heartbreak if you think about it. It's hard not to be just a little sorry for him as he desperately begs for his life (it sounds like he's even crying at some point) totally panic stricken. Even Tiana looks looks shocked and a bit remourseful considering she' just cause his doom.