Because I moved to the "sticks", we have limited internet access. We are so used to having unlimited, that it's a habit to stay logged on. After a few minutes, it will lock us out, but not logging us off. Can I set the computer up to LOG OFF the internet automatically after being idle for a certain period of time?
Assuming this is a dial-up connection, then yes, you can set the connection to disconnect when it has been idle for a certain length of time.
HOWEVER, just because you are not using the Internet does not mean the connection will be idle. If you have automatic updates enabled for Windows and your other software then there will other Internet messages occurring regularly that may keep the connection alive for long periods.