Pirates of the Caribbean: At Worlds End - Hans Zimmer
Jurassic Park - John Williams
E.T. - John Williams
Harry Potter and the Prisoner of Azkaban - John Williams
Titanic - James Horner
Avatar - James Horner
Twister - Marc Mancina
Donnie Darko - Michael Andrews
Dinosaur - James Newton Howard
But my favourite theme comes from a different film...District 9. Clinton Shorter did the score.
http://www.youtube.com/watch?v=kD8LcP3m8fg