my mtu value is on 0 try changing that. all i did to my wii was find the home hub typed in the key and away i went.
From Nintendo's Website: Try adjusting the "Channel" your wireless router broadcasts on. We highly recommend setting your wireless router to either channel 1 or 11. This can potentially increase the download speed. For information on accessing your router's settings, click here to select the brand name and model number of your router (if available).
Rep me if i helped (green mushroom)