The King and Queen in the "Waiting for the Lights" scene. D'awww! Don't cry, sad king!
The heartwarmer is in the look between the King and Queen beforehand. Very reminiscent of the "I'm not strong enough" scene in The Incredibles. They're heartbroken, but keep each other together.
And of course, when Rapunzel reunites with her mother and father in the end. There's a moment when Flynn/Eugene is on the outside of the family's joyous hug, looking on and smiling... then the Queen looks over at Eugene and extends her hand. Eugene goes in for the assumed handshake, when the queen suddenly pulls him into the tight, warm embrace. It's simultaneously a gesture of thanks for saving Rapunzel and a welcoming into the family.
When the Queen and Rapunzel reunite; the King remains at the door, but the Queen is the first to move — she's a mother regaining her daughter!
It also adds to the fact that Eugene is an orphan. He may have never known what it is like to have a mother and father. Now he does.
The fact that after all those years and despite not having her golden hair the Queen still recognizes her daughter.
After all those years a guard runs into their room, and the first thing the Queen and King thinks is that their daughter was found, and they need only a small nod to make it real.
Another very sweet thing about the reunion at the end is just the look on both Rapunzel and the Queen's faces. It's one of those moments where you see the family resemblance, and it's the first time you see it with a direct comparison now that Rapunzel is an adult herself. The look of shocked, wary hope on their faces is beautiful.
Throught the movie, Gothel always makes Rapunzel come to her for a hug but at the end of the movie it's the Queen who initiates the hug between herself and Rapunzel.
Rapunzel hugging Eugene in relief after her tear heals him. And before that, as he is dying, they both say that they are each other's "new dreams". D'awww.... Also doubles as a Tear Jerkerwhen Eugene is dying. *Sniff*
Flynn's character really begins to grow after the scene where he confides that his real name is Eugene Fitzherbert and Rapunzel encourages him by saying she likes it better than Flynn. She also takes to calling him by it for throughout the rest of the film - Flynn responds to this well.
Flynn being Flynn, he does brush it off with a casual "you'd be the first", but he pauses long enough before that to make it clear that the comment actually means a lot to him.
Specifically, she phrases it "I like Eugene Fitzherbert much better than Flynn Rider." She isn't just talking about names, she's saying she likes the real him rather than the person he's pretending to be.
There's a moment, right before the lanterns go up, Rapunzel is passing time putting flowers in the water. Flynn is holding out some flowers in his hand for her to pick from and.... the look he's giving her is just too much.
Also, during "I See the Light", Flynn launches the two lanterns that he had prepared-one for Rapunzel, and one for him.
Let's be honest, the entire "I See The Light" scene is one huge Heartwarming Moment, from the flowers being put into the water to the lanterns to the look that is on Flynn's face as he pushes aside the satchel.
Rapunzel's face when she finally sees the lanterns.
The little moment during the "Kingdom Dance" montage where Rapunzel and Flynn are hiding in a little nook, holding cupcakes and smiling at each other.
The entire Kingdom Dance segment, really. Take your pick of Rapunzel and Flynn growing closer, Rapunzel's excitement at getting to explore and have fun around her own hometown (even if nobody knows that part yet), or how she brings everyone together for an awesome dance sequence.
When Flynn wakes up after being tied to the ship. The first thing out of his mouth is Rapunzel's name, and he doesn't stop thinking about her or trying to get to her after that. Considering his dream was to be alone with lots of money, it shows how far he's come as a person and how much he loves her.
And immediately after, when he tries to escape from guards. Why is he escaping? Not so he can keep himself from being hanged — it's so that he can wring out information from the Stabbington brothers. Awwwwww.....
At the end, where Flynn is playfully playing keepaway with Rapunzel's crown. She tries to get it a few times before realizing what Flynn is trying to do, she smiles and they lean in and kiss. While they're kissing, Flynn puts the crown on Rapunzel's head. D'awww.
"Did I ever tell you I have a thing for brunettes?" All her life it's been drilled into Rapunzel that her magic blonde hair is the only thing she's worth, so when it's gone Flynn makes sure to reassure her that she's still beautiful to him.
Even if she's the villain in the story, the sequence where Mother Gothel leaves the tower to go get Rapunzel the paint for her birthday really was touching.
Indeed. While she was mean and emotionally abusive, if you watch, you see little glimmers that show that Gothel does actually care about Rapunzel, and not just as her own personal walking Botox treatment.
Also, the scene where she panics upon realizing Rapunzel is missing. Even if you could argue it's for selfish reasons, nobody goes that crazy over someone missing unless they care for them on some level.
The cute head bump between the Queen and baby Rapunzel in the beginning. Dammit, Gothel, why did you have to go and ruin everything?!
In fact, every moment between the Queen and baby Rapunzel is simply adorable.
Watch Flynn's expression when he hugs Rapunzel after he gets resurrected. For about one second, he frowns just the tiniest bit◊, and holds Rapunzel a little bit tighter. He knows he was this close to losing her, and he never wants to let her go again.
Rapunzel and Flynn reaching for each other during the Kingdom Dance sequence, and then finally meeting at the end, where they stare shyly at each other. It speaks volumes about their growing attraction to each other, and is also very heartwarming.
When Flynn and Rapunzel are in the Snugly Duckling and the seemingly-malicious Snugly Duckling crew is cornering them and despite the fact that Flynn brought her there to get out of the deal, you can see that Flynn is trying to protect Rapunzel. Awww! He does care!
The first kiss. It's clear that Rapunzel has no idea how to kiss properly (lets her nose gets in the way, doesn't seem to realise that she might want to open her mouth) and then Eugene helps refine her technique. It's just so cute and sweet and gah. If that doesn't remind you of your First Kiss, then you did it wrong.
Funny and heartwarming moment: The campfire scene, when Flynn says that Rapunzel won't want to hear about his past because "It's kind of a downer". Cut to Rapunzel scooching closer, paying her undivided attention.
Producer and long-time Disney animator Glen Keane designed Ariel on his wife. What did he design Rapunzel on? His daughter. Aaaaawwwwwww.
And in a meta sense, his daughter is Rapunzel. Claire Keane was also one of the production artists in the film and did all of Rapunzel's paintings, from the tower murals to the chalk drawing in the Kingdom Dance sequence. The idea that Rapunzel painted her walls was even inspired by how Claire also wanted to paint her room as a child.
The King and Queen sent up the lanterns to bring their child back to them. It worked.
Another one (of many) during the the Kingdom Dance sequence; it's easy to miss, but the fact that Flynn/Eugene, a career thief actually buys Rapunzel various little gifts and snacks throughout speaks volumes... (the apples for Max afterwards are a little harder to call).
Rapunzel appears in full bridal glory into the light, smiling that same kind of smile she had through the whole main movie, and giving a sheepish but happy grin at Eugene when she finally reaches the altar.
The look on the King and Queen's faces when they see Rapunzel and Eugene share their first kiss as a married couple. All the more heartwarming when you consider that they didn't know if their daughter was dead or alive for 18 years, and now they get to see her get married.
When the Stabbington Brothers are shown in attendance. Also counts as a Crowning Moment of Funny, given the "WTF"-look on the face of the guard standing next to them.