I don't know about you, but on my end I like to use static IP addresses on my Intranet.

But under Windows Vista and Windows 7, Microsoft have done an incredibly good job at hiding the network connections to make sure you don't temper with them.

The path is as follow:

        Control Panel\Network and Internet\Network Connections

Once you are in there, you can use the right mouse button to get to the usual MS-Windows settings (The one where you can click on IPv6 or IPv4 and setup the IP to static.)