Openvpn – How to make Windows 7 treat a VPN connection to a subnet look like a non-“public” network

I'm torturing myself with the task of trying to get an OpenVPN connection to a work subnet working under Windows 7. After some travail I've gotten the OpenVPN client to work and properly connect. However, though the connection is apparently up, Windows considers the network a "public network" and won't let me browse it. It tells me that I need to change the networks profile (or something) to "Home" or "Work". The problem is that I have no idea how to do that, and I see no obvious place in the Network control dialog(s) to do that.

I suspect this is really simple and obvious, but I've clicked through every link I can find in those control panel dialogs and nothing works. It feels kind-of like playing Myst.