T-Mobile Samsung Galaxy S2 (T989) Lag, Freezing, Unresponsive after ICS Update? Try this.

You should try wiping your cache partions.

Take out the battery
Put it back in
Hold Volume up + Volume down + Power until you feel it vibrate and see the "SAMSUNG"

Let go off power but keep holding volume buttons
this boots you into 3e recovery

use volume down to scroll to wipe cache partions
hit home to select
and then scroll back up to reboot and then hit home

hope it helps 

Thanks toindian9990