http://www.techsuppor...-wireless-network.htm
There is a link to Nir Sofer's page to download it in the article, but read the comments first ! Works fine for me (XP SP3) and detects the wired connection as well as the only wireless one that is running right now.
For the security and restricting access, it's your router which handles that bit, but if you post details of which one it is, I'm sure one of the more tech oriented people will be along soon to tell you how to access the router and set it up