I've got a million of these, but a few that jump out when I'm called on to name them.
In the remake of "The Parent Trap", the scenes when each of the girls reveal their true identities (Hallie to her mother, Annie to Chessie) are both movie-makers.
In "Blade Runner", Roy Batty's death is downright moving.
In "LotR: The Two Towers", the scenes involving the defenders of Helm's Deep preparing for the battle, culminating in Theoden donning his armor, is one of the best build-up scenes I've seen in any movie. "How did it come to this?"
In "The Shining", the part when Jack finally snaps is surprisingly frightening.
In "The Breakfast Club", the scene when the group is sitting on the library balcony discussing their various offenses encapsulates the entire point of the film.
In "Saving Private Ryan", the Normandy invasion was so much more horrifying because I knew it was so realistic. In the same vein, the initial battle scenes in "Enemy At The Gates" were gut-wrenching for exactly the same reason.
In the original "The Karate Kid", the scene in which Daniel confronts Mr. Miyagi about all the work he's made him do, only for Mr. Miyagi to demonstrate that he's been preparing him all along made a good story into a great story.
In "Jurassic Park", the moment when John Hammond reveals the true nature of the park always gives me a huge sense of wonder.