I downloaded the trailer and ran it in Quicktime and VLC. VLC? No problems. Quicktime Player 7? Stuttering and freezing. Quicktime Player (Mavericks)? Perfectly fine. My specs of my iMac are in my signature.
EDIT - Edited because I forgot to post the Quicktime Mavericks bit!
EDIT - Edited because I forgot to post the Quicktime Mavericks bit!