Save settings for direct cable connection?

I connect my laptop and desktop via ethernet cable to sync files. How do I
change the default setting from public to private for this type of
connection? I routinely connect my computers this way, and I would like
Vista to remember the connection settings. It is a huge hassle to change the
setting from public to private on both computers each and every time for the
transfer to work.

How can I set up this connection permanently, so that the computers remember
it when I reconnect them?

The reason I do this is because both computers have gigabit ethernet, which
is loads faster than wireless or through the 100 mbps router.