James newton Howard's work in Blood Diamond was one of the best, Check out the last act in that film, it's tragic and uplifting at the same time.
Hans Zimmer's work in The Lion King, Gladiator, The thin Red Line(check out the song Journey to the line), Tears of the Sun, The Rock, Crimson Tide, The Last Samurai, The new Batman Films are all great, even his lesser known scores in the films Days of Thunder, Backdraft, Toys, Pearl Harbor are pretty epic I have pretty much bought everything he has produced. Zimmer, he really knows how to capture the "final moments" of a scene and characters.
Another favorite is Alan Silvestri all of his early work was extraordinary. He did the Back to the Future scores, Predator, Cat's Eye, Who Framed Roger Rabbit, Ricochet, Judgement Night, He could be one of the great "suspense" composers.
John Williams of course, he did Stars Wars, Indiana Jones, Jaws.
James Horner Honey I shrunk the kids, Willow, Krull, Aliens.