Hollywood today is mostly about sequels/prequels, remakes, reboots, adaptions and spin-off. Titanic is based on real events, Avatar is not really original (As pointed out by Sean in the comments) and frozen is based on the snow queen. So, technically none of the top 10 are originals. But I never complain as long as the movie is fun and entertaining. Except Titanic, that ending was really depressing.