Ad-Hoc network, XP and Wii

So, my girlfriend recently got a Wii and I'm trying to set up an Ad-Hoc WLAN to give it intarwebbars access. We've got her XP MCE SP2 laptop plugged into the wired network. I've tried going to Network Connections-->properties for wireless-->wireless network tab-->add network under preferred networks, click the ad-hoc checkbox, etc.

However, this does not seem to get her laptop to actually *transmit* a wireless signal, but rather it wants to look for an ad-hoc network going by the SSID I gave it. When I tell the Wii to look for networks, it doesn't find this network (though it can see other nearby ad-hoc networks).

Tips would be appreciated!