Whats a good program for a parent to monitor a teens internet usage, email, chat, etc?

What software have you used for this purpose? Which one do you like? Did you get satisfactory results from it? Its doesn't matter if it`s a free or pay program. I`m interested in one with a key-logger as well as screen capture capabilities so that I can monitor typed conversations, login and password entries, websites visited, videos viewed etc. It must also be capable of running in the background without alerting the user to its presence. A nice feature would be if it could email me the results of screen-caps and key-logs, but this is not required, since I have full access to the child`s computer. I did a quick search and was surprised at the number of programs out there all claiming to do what I want. So instead of trying out a dozen until i find one that works for me, I figured I`d ask other parents who may have used these before. To see what programs work best and which ones you like.