“I was cured, alright!” as Ode to Joy swells
A Clockwork Orange
or:
“The dead know only one thing. It’s better to be alive.”
Cue “Paint It Black”
Full Metal Jacket
Glad somebody else like this as much as I do 
I went out and got a Monet print after seeing that.
I’ll mention “Mr. Brooks”, starring (and produced by, IIRC) Kevin Costner. Not a perfect movie, but definitely a decent thriller with a heck of an ending, featuring a haunting song to go with a shocking visual.
Das Boot, amazing finish.
To Die For, very satisfying end.
One of Costner’s best movies, actually. Shame it wasn’t a bigger hit. Good call.
The closing credits for the first Chronicles of Narnia movie. Imogen Heap’s “Can’t Take it in” with Harry Gregson-Williams’ orchestral treatments, the little dialog between Lucy and the professor, the roar of Aslan, then the angelic “…it cannot be…anymore beautiful…”. I was like, “Wow”. The other closing credit songs by Alanis Morrisette and Tim Finn were good, too.
The Vanishing (original version–I hear the remake changed the ending) is my all-time favorite ending.
I’m aware.
So did Wedge and the sole Y-wing pilot.
In Stephen King’s novella Apt Pupil, Todd’s teacher confronts him, and Todd reacts by shooting him and going on a killing spree.
The movie’s ending is scarier.