Situation has to come into the decision here though - in a large MTT if you are short stacked with AA, surely the correct move is to push preflop. The re-raiser is likely to put you as a shortie on a wide range and will call more often than fold, meaning you achieved the desired result of all in with a caller whilst you are ahead.
However, if you are deep stacked, then a smooth call might be a better option if only one other player in pot - you give him the rope to hang himself if he hits the flop sideways... but also you are not committed to the hand and can get away from a scary board.
BUT in a cash game at any level, I"m nearly always re-re-raising preflop to give the other guy the option of pushing back again. In a headsup situation, AA will win most of the time against any two cards, hence I want the opportunity for all the chips to get in preflop whilst it is in the lead. He might have QQ/JJ, and if the flop comes with overcard after your smooth call, any decent player should be able to fold the QQ/JJ..... get all the chips in preflop and he doesn"t have the option. It"s also amazing how many people are prepared to stick all their chips in the middle preflop with AK in cash games - smooth calling denies them the opportunity to do so.