The confrontation between Noodles and Max at the end of 'Once Upon a Time in America'. For about ten minutes, there's barely any action, and the characters barely say a word. But at the same time, the sheer tension of the moment, all the little half-glances, they all just make the moment probably the most intense and... brilliant of any movie I've seen.
The shootout at the Central Station in 'Untouchables'. That scene on the staircase is practically legendary, and so it should be. Brilliant cinematography.
The torture and beheading, and subsequent epilogue from 'Braveheart'. If you're not moved by that scene, you're a statue and cannot be reading this in any case.
The ending to the 'Truman Show' was just stunning. Jim Carrey and Ed Harris will not get better than that movie.
Lastly, and from this list least, the destruction of the Russian battalion from 'Turkish Gambit' (It's a Russian movie). It very well may be the best blend of skilled camera work and CGI effects I've seen in a Russian movie, and maybe of any film.