How do I put a 4 plex security cam system on motion detection system?

I have a system from supercircuits with a 4 cam color quad processor and a 1280 hr time lapse VCR recording and I would like to hook it up to a motion detector on each cam and replace the VCR with a Presidian PDR 3222 DVD recorder. Also having trouble with DVD Recorder not opening to insert a DVD. It would be a great great help if someone can help me with problem? I am not very tecnacial so any pic or video would be a great help if possible. Thank you for any help in advance.