If you have XP, create a user account for “him” and setup the group/user policy so he can’t do harm. Much better way. No need to bring a security risk to your comp with a keylogger.

Look HERE for many security options you can set.

Using a keylogger will not “keep him out of harms way”. He first does things, gets in trouble and only then you see it. Better prevent him from getting into troubles.