400NL: AQo on SB, call the river?

You say Villain is LAG preflop, but what is he like post flop? If you think he will make this play any time you check the turn and river, then you should call. But if that's not the case, then I don't think you're beating much here. You're not beating A-10, A-Q, A-K, K-Q, K-J, Q-J, or even K-x. That's assuming he didn't flop a monster hand. So basically you're only beating a total bluff. so if you think he's on a complete bluff as often as not then you can call, but you can't beat anything but a bluff.