Should I have bet the river?

[PuertoKid]

I hadn't had much time at this table. There were two posters and I was cutoff with 77. I wanted to attack this hand hard because of the dead money. I'm wondering if I should have bet the river.

Party Poker 1/2 Hold'em (10 handed)

Preflop: Hero is CO with 7[img]/images/graemlins/club.gif[/img], 7[img]/images/graemlins/heart.gif[/img]. MP1 posts a blind of $1. MP3 posts a blind of $1.
UTG folds, UTG+1 calls, UTG+2 folds, MP1 (poster) checks, MP2 calls, MP3 (poster) checks, <font color="CC3333">Hero raises</font>, Button folds, SB folds, BB folds, UTG+1 calls, MP1 calls, MP2 folds, MP3 calls.

Flop: (10.50 SB) 8[img]/images/graemlins/club.gif[/img], 2[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/club.gif[/img] <font color="blue">(4 players)</font>
<font color="CC3333">UTG+1 bets</font>, MP1 folds, MP3 folds, <font color="CC3333">Hero raises</font>, <font color="CC3333">UTG+1 3-bets</font>, Hero calls.

Turn: (8.25 BB) 9[img]/images/graemlins/heart.gif[/img] <font color="blue">(2 players)</font>
UTG+1 checks, <font color="CC3333">Hero bets</font>, UTG+1 calls.

River: (10.25 BB) 4[img]/images/graemlins/diamond.gif[/img] <font color="blue">(2 players)</font>
UTG+1 checks, Hero checks.

Final Pot: 10.25 BB