two pr vs an unknown crowd

[Guruman]

I'm about ten hands into this session. A couple of people are showing fishy tendancies, but nothing close to a decent read on anyone yet.

Party Poker 2/4 Hold'em (10 handed) converter

Preflop: Hero is SB with Q[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/club.gif[/img].
<font color="#666666">2 folds</font>, UTG+2 calls, MP1 calls, <font color="#666666">3 folds</font>, Button calls $1 (All-In), Hero completes, BB checks.

Flop: (4.50 SB) A[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(5 players, 1 all-in)</font>
Hero checks, BB checks, <font color="#CC3333">UTG+2 bets</font>, MP1 calls, <font color="#CC3333">Hero raises</font>, BB folds, <font color="#CC3333">UTG+2 3-bets</font>, MP1 calls, Hero calls.

Turn: (6.75 BB) Q[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(4 players, 1 all-in)</font>
Hero checks, <font color="#CC3333">UTG+2 bets</font>, MP1 calls, Hero calls.

River: (9.75 BB) 8[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(4 players, 1 all-in)</font>
Hero...

flop is questionable, but I have no idea how to play this hand if I lead out and it gets called around.

check/call or bet/fold this river?