The original Highlander movie more or less codified the Crowning Moment of Awesome with the Quickening (No, not the awful movie). What could we do to make a swordfight more awesome? Oh, how about when one of the guys takes the other guy's head, EVERYTHING EXPLODES!
The church scene in the original film. Never before has two men sitting down and talking been more badass.
Conner defeating the Kurgan.
The duel between Ramirez and the Kurgan. When Sean Connery is demolishing brick walls due to the impact of his sword, you know that Awesome is occuring.
The gun nut who stumbles upon the end of a duel and opens fire on the Kurgan. No, it didn't work, but he still did better than just about anyone else who went up against the Kurgan.
Say what you want about Endgame, but The quickening Duncan gets from killing Jacob Kells is awesome
As with "Highlander 2", say what you will about the film, but goddamn, Michael Ironside was just so awesome as the over the top evil Katana, you can tell even with what he had to work with, he was having a ball.