Fastest way to split a video file into two?
You might also be able to do this using Quicktime X. Open the movie, then choose Edit -> Trim... Trim away the second part of the movie file and do a save as to get the first part in a separate file. Re-open the original file and trim away the first part, save as to get the second part in a separate file. 

I've only been able to try it with a 5 minute long movie, which was quick enough, but I'm unsure of how quickly it'll work with a 2 hour movie.