AJs check the turn?
 

PokerStars 2/4 Hold'em (6 handed) converter

Preflop: Hero is SB with J[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/spade.gif[/img].
<font color="#666666">2 folds</font>, CO calls, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises</font>, BB calls, CO calls.

Flop: (6 SB) 8[img]/images/graemlins/diamond.gif[/img], 2[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets</font>, BB calls, CO calls.

Turn: (4.50 BB) 9[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, <font color="#CC3333">BB bets</font>, <font color="#CC3333">CO raises</font>, Hero folds

BB is a LAG, no reads on other player. Do I check the turn? What should I do if 1) BB bets, CO folds? 2) BB check, CO bets? and 3) BB bets, CO calls?

Lots of questions but I would like to know what to do in different situations that could occur