How are you measuring the speed? 12Mbps is a strange speed for a "wired" connection because, if you have a 20Mbps connection, it is very slow. With a 10Mbps connection, it shouldn't be that high. ????
The "port" speed as shown in the computer should obviously be 100Mbps wired and 54Mbps wireless.
As regards the 2Mbps wireless speed, try changing the Channel in the router's settings to see if interference on the existing Channel is causing the slow performance.