Is it the nail-biting finale in which the cornered Warden Norton (Bob Gunton) threatens to blow up the prison killing all of its inmates with the tons of explosives he has deviously placed under the prison foundations?
Is it the thrilling final battle on the roof of the prison block between Andy Dufresnse (Tim Robbins) and the dastardly Captain Handley (Clancy Brown) in howling rain amidst flashes of lightning and a vomit-inducing virtual camera spinning around the roof in circles?
Is it the brilliant cliffhanger ending when Ellis (Morgan Freeman) reaches the beach at the movie’s end only to discover a note that Andy has been captured and incarcerated in another prison, and that cinemagoers now have to go watch another movie in which Ellis breaks his friend out of prison, in SHAWSHANK II: ANOTHER REDEMPTION?
Well no, funnily enough it has become incredibly popular possibly because its none of the above.
the ghost of 82 
You had me for a minute there — “damn, I don’t remember that bit. I really must rewatch it…”
Maybe in the inevitable reboot/remake starring The Rock and Jason Statham….