My pick is Stanley Kubrick's 1968 masterpiece, 2001: A Space Odyssey.
Also Sprach Zarathustra by Richard Strauss will forever be one of cinema's greatest opening themes. And combined with the opening credits of the movie with the sun rising slowly over the Earth was absolutely groundbreaking and legendary. It is truly one of the greatest opening credits sequences of all time.
My God, I have not been more bored watching an action movie. I actually turned it off because it was putting me to sleep and I just thought the whole thing was dumb.
I could list a bunch of movies but it's easier to say anything scored by John Williams. Superman, Star Wars, Raiders of the Lost Ark, Jaws. I never caught Close Encounters of the Third Kind but I'll go out on a limb and say it's good just on faith.
He scored some other things, but that's what I remember off the top of my head.
My all time favourite is Lord of war. Perfect song, nice way to show the bullet production and then in the end when it hits its target... Could not imagine a better opening to this movie. Especially once you get to know that it is based on some real russian arms dealer.