What kind of video camera do i need to suit my needs?

The battery life is an issue. Do you need to sleep for 10 hours? There are a lot of cameras that might suit your needs. A pinhole nanny camera would be the easiest to conseal, but for long recordings you might want something that is plugged in. You might even want a nightvision camera. I attached a link for a mini DVR with built in motion activaded nightvision camera. It says 3 hours battery life, but if no motion triggers it to record, it should have a good 6 hours of life. You could also use a web cam with your computer. I attached a link to an article that explains how. If you go to the hardware store you can also get a simple electric door alarm that chimes when the door opens.