Depends how the netgear router is configured. You need to get into the router config (type in 192.168.1.1 OR 192.168.0.1 in your internet browser to get to the router login page - you'll need the username and password combination, which is usually admin/password).
From there you need to find out if its broadcasting its SSID aka the wireless network name (this could be the reason your card isn't picking it up, if the router isn't broadcasting its presence then you'll get nada when you search for it). Also, is encryption enabled, if so, is it a kind the wanadoo card can support? WEP is the least secure, but most common form of wireless encryption there is. Make a note of the passphrase or the key with all the numbers and letters and you'll have to put that in when the card finally does detect the network.
Ummm..kinda hard to give more advice without more info. See what you can do with what I've told you and we'll take it from there.
Xander