Star Trek is a symphonic melodic fantasy score that deserves to be listened to. There are at least 4 main themes that are gorgeous and have plenty of splendid apparitions. Nero's theme is a wonderful dark tune, particularily when it is reprised by the chorus.
Night at the Museum 2 is a great fantasy/adventure score with many moments a la Mummy Returns. The melodies are catchy in the great tradition of Alan Silvestri.
That makes at least 2 memorable examples for this year alone and the summer hasn't begun.
But last year, what about The Mummy 3, The Chronicles of Narnia 2, Journey to the Center of the Earth, Speed Racer, Indiana Jones 4, City of Ember, The Tale of Despereaux, The Bridge to Terabithia... All are memorable melody driven adventure scores full of roller coaster cues. You truly missed something here !
