99 under-pair in a field of 5

[Fnord]

UTG+1 is LA-P
CO bought in for the full $100, but otherwise unknown

Party Poker 2/4 Hold'em (10 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

Preflop: Fnord is MP1 with 9/images/graemlins/spade.gif, 9/images/graemlins/club.gif. CO posts a blind of $2.
UTG folds, UTG+1 calls, UTG+2 folds, <font color="CC3333">Fnord raises</font>, MP2 folds, MP3 folds, CO (poster) calls, Button calls, SB calls, BB folds, UTG+1 calls.

Flop: (11 SB) K/images/graemlins/diamond.gif, 2/images/graemlins/heart.gif, 2/images/graemlins/spade.gif <font color="blue">(5 players)</font>
SB checks, <font color="CC3333">UTG+1 bets</font>, <font color="CC3333">Fnord raises</font>, CO calls, Button folds, SB folds, UTG+1 calls.

Turn: (8.50 BB) J/images/graemlins/club.gif <font color="blue">(3 players)</font>
UTG+1 checks, Fnord checks, <font color="CC3333">CO bets</font>, UTG+1 calls, Fnord folds...

[Noodles]

Well UTG cant be betting a flush/str8 draw and when someone bets into a pfr it usually mean they have top pair and are testing you out, did you rais eto try and get a free river card and get to the end cheaply,
i think folding the flop wouldnt be a bad move

[Noodles]

i think this is a very common situation and was wondering the right way to play it?