I dont mind limping preflop with AA. But it's usually more appropriate for you to bet the flop. I don't see how he could have a top pairish hand that he'd want to check on the flop (unless he slowplays top pair heads up) and wants to bet big on the turn when the falls. AA will win 80% of the time, but most of the time that's becuase the opponents hand doesn't improve and thus he won't pay you off.

Also, by raising a little preflop you atleast make a pot that he might wanna go after if you lead on the flop weak. Just some thoughts.

-'rilla