If you’re going to do the TiVo route, do a little research on tivocommunity.com first. For the tivo to work without a subscription it MUST be a series 1, and I think it even has to be manufactured before a certain date (that’s the part to check), other then that, it works, I’ve done it.
Here’s a tip if you go that route, wait, two tips. First tip is if your camera feeds into the composite video in, tune the TiVo to channel 0 to get the feed.
Second tip, set up 12 2 hour recordings to span the day (12-2, 2:00-4:00. 6:00-8:00 etc) This does to things for you, it allows you to find something easier. If you know it happened around 2:15 yesterday, you can just click on that ‘episode’ and find it, second, after a few days it will fill up, then each time it starts a new ‘episode’ it deletes the oldest 2 hour chunk, instead of an entire day. You could do this on 1 hour chunks as well, it’ll just take longer to set up.