Flop nuts in unraised pot, board pairs facing AI river bet - ADVICE?

[orig!naL]

Villain is 52/18/1.5 over 65 hands.

I found this river decision really tough considering it was an unraised pot. I think I have to call this river, but when I got min-raised on the turn I really started wondering if this guy just filled up.

I really felt my flop call was fine considering the CO is also a huge calling station and I wanted to try and get a little more action (given I just flopped nut straight on a dry board). I do however think it may have been smart to shove the turn? Thoughts?

Do you guys call this big river bet or lay down your flopped nuts, confident you are beat?

Full Tilt Poker - No Limit Hold'em Cash Game - $0.10/$0.25 Blinds - 6 Players - (LegoPoker Hand History Converter)

SB: $36.60
Hero (BB): $35.70
UTG: $16.70
MP: $21.90
CO: $49.60
BTN: $24.75

Preflop: Hero is dealt (6 Players)
UTG calls $0.25, MP folds, CO calls $0.25, BTN calls $0.25, SB calls $0.15, Hero checks

Flop: ($1.25) (5 Players)
<font color="red">SB bets $1.00</font>, Hero calls $1.00, UTG folds, CO calls $1.00, BTN folds

Turn: ($4.25) (3 Players)
<font color="red">SB bets $2.00</font>, <font color="red">Hero raises to $6.00</font>, <font color="red">CO raises to $12.00</font>, SB folds, Hero calls $6.00

River: ($30.25) (2 Players)
Hero checks, <font color="red">CO bets $25.00</font>...