Security system camera systems can be had for pretty cheap these days. A four camera system with DVR can be had for under $200, and now even less than $100 in some cases. You may be better off with that system.
Security Spy is one possible program, with older versions available for older macs. I'm not sure what the camera compatibility is.
http://www.bensoftware.com/securityspy/
http://www.bensoftware.com/securityspy/download_prev_version.html
It appears to have all important security camera software functions (or at least the newest version), like recording only if motion is detected and programming alerts. (For example, if motion is detected during a certain time it will send you an email).
Due to a home invasion/attempted robbery that occurred 3 years ago at 3:00AM when I was home alone (parents, siblings, & dog were on vacation), my parents installed security cameras. The police were unable to apprehend or identify the criminals. They now have 10 exterior cameras covering all entranceways, garages, driveway, and pool. It's a bit much if you ask me, but I will say it did make me feel safer after the trauma of a home invasion. We had a security system, but was not armed because I was home.
The system they use has it's own DVR that actually has pretty decent software. It has a 20" LCD for viewing but the video can also be accessed over the local network (or remotely if set up). They can be set to record motion only and programmed to send email alerts. This seems to be pretty standard with even with the cheap models now. The price goes up for higher quality cameras, power over ethernet cameras (less wiring, especially if your house has ethernet), more storage space, etc.
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Interesting.
Oh, iMovie would record video directly from a camera. Try iMovie!
I have a suspicion that after hours of recording, iMovie would get bogged down and freeze. I remember recording VHS tapes to iMovie back in the day using a analogue to firewire digital converted on 800mhz-1ghz iMac G4s. After sometime it would get bogged down. The best method was to do it in chunks. iMovie may have improved since then though.
