All the security cameras I have seen that record to memory card are IP cameras that you set up by logging in to them with a web browser so not really going to be much use without any wifi or wired network.

A wildlife camera might be the best solution as these have a PIR detector that detects movement and then records for a period of time to a memory card and works for a few months from batteries.


These type of products:
www.ukwildlifecameras.co.uk/trail_cameras/standard_trail_cameras__C168.html

www.wildviewcameras.co.uk/swann-outbackcam

Yes Foscam do some good stuff and low prices, wont be easy setting up without any network.

A old router with wifi could be set up at pre65's mothers house just to provide wifi and DHCP etc for a laptop and camera, should work even without a connection to the internet (possibly)