Hi and welcome,
First check that your card is correctly detected and that it works, to that end, open a terminal and type 'sudo iwlist scan' (if it tells you that the network interface is down, just type 'sudo ifconfig <name of interface> up; name of interface being usually wlan0, occasionally ath0 or eth* )
No changes should be needed on your router, try configuring you car using the GNOME utility (double click on the network status icon, top right if I remember correctly) or try following
this guide.
Have fun with linux..
Serafean