1. ZIP. A file compression tool/method
2. MP4. A video format.

Your version of OS X will take care of the ZIP process for you while a program called Handbrake should take care of the other problem.

No guarantee about keeping stuff in the same organized folders though.
Once you unZIp a file, you have two files. The original and the unzipped version
Once you convert a video file, you have two files. The original and the converted file.

I feel that you will be the one to do the organizing

P