Bottom set on monotone flop, lay down or move in?

[redrooski24]

Party Poker No-Limit Hold'em Tourney, Big Blind is t15 (10 handed) converter

Hero (t1090)
CO (t955)
Button (t1045)
SB (t955)
BB (t1010)
UTG (t985)
UTG+1 (t2000)
UTG+2 (t985)
MP1 (t915)
MP2 (t1060)

Preflop: Hero is MP3 with 3[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/club.gif[/img].
<font color="#666666">1 fold</font>, UTG+1 calls t15, <font color="#666666">3 folds</font>, Hero calls t15, <font color="#666666">2 folds</font>, SB completes, BB checks.

Flop: (t57.50) 9[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, <font color="#CC3333">BB bets t45</font>, UTG+1 folds, <font color="#CC3333">Hero raises to t120</font>, SB folds, BB pushes, Hero...

How sure do I need to be here that he's got a made flush for me to fold? This is a $33 on Party so I leaned towards a call but I'm not quite sure if I should be making these calls.

Also - why the hell can't I get the damn converter to work? I cut out the Texas part of NL Texas Hold Em but still no go.