(55) playing a baby flush

[Slim Pickens]

Party Poker No-Limit Hold'em Tourney, Big Blind is t15 (9 handed) internettexasholdem.com

UTG+1 (t945)
MP1 (t1890)
MP2 (t990)
MP3 (t895)
CO (t975)
Button (t985)
SB (t1320)
Hero (t1000)
UTG (t1000)

Preflop: Hero is BB with 6[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">1 fold</font>, UTG+1 calls t15, <font color="#666666">4 folds</font>, Button calls t15, SB completes, Hero checks.

Flop: (t60) 2[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">SB bets t30</font>, <font color="#CC3333">Hero raises to t85</font>, UTG+1 folds, <font color="#CC3333">Button raises to t250</font>, SB folds, Hero calls t165.

Turn: (t590) 8[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets t320</font>, Hero calls t320.

River: (t1230) T[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, Button checks.

Final Pot: t1230

Obviously I need to be raising this flop, but I've got less of an idea of how to react to the reraise. Anyway, I suck at playing "poker," so help me out.