If he's using DL dvd's he should be able to get two hours on it easily. Size and time are directly related by the compression algorithm used to encode the video. If he recompressses with lower compression ratio it fits regardless of time.
Yes, there are utilities for splitting, combining, shrinking, removing subtitles, just about anything you want to do. Some are free some are ~$29.
I repeat it can be shrunk to fit in a 2 hour dvd play time. (Or if you prefer split.)
But since Constantine is not out in DVD yet you are asking for help with a crack...
Bye.
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