Picture this, someone has to connect to someone else, that's P2P.
To connect to someone you need a open port to connect to.
If both sides are hiding behind a firewall and are too stupid to learn to open a port, neither can talk to the other.
So stop running windows and quit being scared of every little hacker out there. Bill gates has known about all these security issues for years and hasn't done anything about them, why would you want to run a pile of crap OS like that?
Dump his crap. New Red Hat and Mandrake are out and include lots of already loaded software like word processors, browsers and more.
All for FREE!