With apologies to Ronald, I'm swiping his comic book movie theme. That's what I do here, I lurk and I steal.
Some comic movies are good, some are not; but that's beside the point. Making a whole movie adaptation good is tough to do, anyway. This is about those scenes...those great scenes...that just perfectly encapsulate the character. A comic movie can be 90% garbage (I'll refrain from naming the ones I'm thinking of, but they are many and great in number) and still contain that one perfect scene. Here are my top five.
(I had to exclude several good comic movies, such as Hellboy and the Crow, because I'm unfamiliar with the source material. And in the case of Sin City, everything's lifted straight from the comics anyway)
5. Reed and Ben (Fantastic Four)

The newly-dubbed Fantastic Four have just saved a bunch of lives on the Brooklyn Bridge (lives which they initially put in danger, but that's neither here nor there). Among the cheering onlookers, Ben Grimm sees his wife looking at him, horrified at his new appearance. She removes her wedding ring, lays it on the pavement, and leaves. Ben tries desperately to pick the ring up, but his rocky fingers are too big to close around the tiny ring. As Ben grows more frustrated, Reed Richards picks the ring up and drops it into his friend's palm.
Reed: "I swear to you...I will do everything in my power until there is not a breath left in me. You are going to be Ben again."
Among the relationships in the Fantastic Four -- the love between Reed and Sue, the sibling angst between Sue and Johnny, the friendly rivalry between Johnny and Ben -- the friendship between Reed and Ben is arguably the most important. Ben, the heart of the team, is in a constant state of heartbreak because of his condition. Reed, the brains of the team, is wracked with neverending guilt over his greatest mistake. But despite this, their friendship only grows stronger, and their flaws push both men to better themselves.
4. Batman Begins

After their shared experiences saving the city, Batman and Lieutenant Gordon have entered into a tenuous partnership. They're not yet the friends they will become, but there is mutual trust and respect between them. Just before Gordon sends Batman off on a new case, he stops him to say:
Gordon: "I never said thank you."
Batman: "And you'll never have to."
Batman is not driven solely by revenge. There is also a great desire in him to protect, to build, and to better the lives of those around him. His Bruce Wayne is a concerned citizen, not just a mask. As Jeph Loeb would say, he believes in Gotham City. It's not simply his protectorate...it's his home.
3. Professor Xavier (X-Men)

After Magneto's defeat and imprisonment, Charles Xavier visits his old friend in jail for a game of chess and some light philosophical debate. A classy thing to do, all things considered.
Never missing an opportunity to needle Xavier, Magneto asks if he ever worries about the future. If he ever dreams about radical humans coming for his children in the night.
Magneto: "What do you do, when you wake up to that?"
Xavier: "I feel a great swell of pity for the poor soul who comes to that school...looking for trouble."
That right there reminds everyone that Xavier, besides being a kind old teacher, is a total badass. He is a gentleman and a scholar; he hopes for peace and he strives for unity; but anyone comes after his children, and he will fry their brain like an egg.
2. Constantine

Father Hennessy hears the voices of the dead and damned...quite against his will. It got so bad that he developed a drinking problem, and took to wearing a medallion that kept the voices out of his head. Unfortunately, John Constantine decides he needs those voices. With a huckster's smile, he takes the protective medallion off of Hennessy and slips it into his pocket.
Constantine: "C'mon, you don't need its protection. It'll be like back in the day."
It's a scene fans of Hellblazer have seen many times before...John sending a friend to his death with a smile on his lips. It's not that he doesn't care about his friend, or even like he's gambling with his life. It's just that John Constantine needs something, and for that moment, that's the only thing in the world that matters.
1. Superman

After saving California and the fair Miss Lois Lane from destruction, Superman scoops up Lex Luthor and drops him off in jail. The prison warden commends Superman for his service to the world.
Warden: "This country is safe again, Superman, thanks to you."
Superman gives the warden that "aw, shucks" smile, sort of salutes him, and slowly flies away.
Superman: "No, sir. Don't thank me, Warden. We're all part of the same team. Good night."
What's so great here is you honestly believe what Superman is saying. In his mind, there is absolutely no difference between what he does, and what the warden of a prison does. They're all good guys. And when the most powerful being on the planet considers regular ol' humans his equal, that's pretty cool.