Problem connecting to internet on laptop

I have a problem accessing internet through "Peak wireless router"

system is dell laptop with xp.
everything was working fine for 2 years untill I Formated drive C. I reloaded XP (service pack 2) then all the drivers. WiFi seemed to hang on "acquiring IP address". I could see I was getting a full strength signal. reset Password on both Laptop and PEAK, ensuring both set to WPA encryption, no effect. uninstalled Wifi drivers, re-installed, same problem. Did it again same problem.
Connected ethernet (wired), Here we go, no problem. straight on to internet. However....
WiFi still hangs on "acquireing IP address".
Downloaded XP (service pack 3) and IE 8, Installed, latest Wifi driver from Dell, still hangs.Changed from Dynamic IP address to static, not the most ideal, But Hey.
Now I can see my home network, and access other computer. still no Internet. changed from IE8 to Google Chrome, Still Nothing?
Anyone got any ideas?