(Newbie grunch)
This is a big pot (raised and 4-handed pre-flop), so I would probably raise for two reasons. 1) I want to fold out the sb and bb, and 2) I would like a bit more info from Mr. LAG. If he has a Q, a 2, or a draw, I would like to be able to spike my K or J to win, and folding the blinds would help this, IMO. If he has an A, we have 4.5 outs to beat him, and our bdf is to the nuts. I would assume that this could also count as a semi-bluff, although LAGGy prob won't fold. If he 3-bets, I would prob call and fold the turn UI.