daft related question
is broadcast SSID enabled and wifi enabled within the router
i'm assuming you can get into the router management pages ok
what is it showing for the status of the wlan?
if you can access the router page and wlan is configured correctly, first rule out that its not the laptop refusing to pick up the signal by using another wireless device
if that doesnt work then i suspect the wireless chip will have fried or the signal is not strong enough anymore (possible if the antenna is damaged)
if its the wifi chip then sorry not a lot you can do about it here, would be quicker, and more reliable to get a new router, in most cases the better spec will also be good too