What to do to fix wireless network adapter?

I am running Vista Home Premium on a Compaq Presario F500 laptop. On the front of the laptop, there is a switch which is supposed to turn the computer's wireless adapter on and off (a light turns blue when on, orange when off). The switch recently stopped working; no matter which position it is in the light is orange and I cannot connect to wifi.

When Windows diagnoses the connection, it recommends updating the drivers for the adapter, first via Windows Update (which did not work) and then manually by opening the Device Manager. In the Device Manager, under Network Adapters, I see "NVIDIA nForce Networking Controller" and "Teredo Tunneling Pseudo-Interface". I attempted to update the drivers for both but a window appears saying they are up to date.

The icon for the adapter "Teredo..." has a yellow triangle w/ exclamation point and clicking on it from the Device Manager gives the message "This device is not working properly because Windows cannot load the drivers required for this device. (Code 31)"

When plugged into a router, the computer connects to the internet without a problem, but it will not connect wirelessly even after restarting and switching the adapter switch off and on. Any suggestions?

If no one has suggestions as to how to fix it, any advice on where to go to have it looked at? Will fixing it probably be relatively expensive?

I have no idea how serious/common of a problem this is...

The switch could be bad if your laptop is still under warranty send it to HP and get it fixed. The Teredo is for p2p applications that uses IPv6 so you don't need to worry about that.