get connected....
http://axion.physics.ubc.ca/ppp-linux.html
router.....
setup iptables for masq, once you get it setup you can do things like port forwarding, which you will not be able to do otherwise.
required for some things to work.
network file shares....
setup samba so you can view everything in network neighborhood and share files.
maximize speed.....
setup a dns server, and squid proxy.
maximize your connection on your windows boxes by trying tweeks to the tcp window size, mtu and browser server settings in the registry.