These are truly the Masters of Movie Music. We we can not compare them, becouse they are all God in the genre they work in.
Isaac Hayes
Master of blaxploitation-music.
Ennio Morricone
Master of spaghettiwestern-music.
John Williams
Master of adventure and drama-music.
Bernard Herrmann
Master of horror-music.
This list is far from complete. Help me complete it.
Isaac Hayes AND Quincy Jones
John Williams AND Hans Zimmer and probably Jerry Goldsmith from the same category too.
Danny Elfman is a very talented more recent composer too.
And in the italian composer category, to add with Ennio Morricone : Nino Rota, Carmine Coppola cause you cannot watch The Godfather without, and Pietro Mascagni who was more an opera composer (and maybe only that) but you cannot watch Raging Bull without his splendid compositions.
Bill Conti - The Karate Kid and Rocky!!!