How Not To Extract Value

Managed to win the minimum here. Surprised this guy checks behind a 5 on the river.

POKERSTARS GAME #20419426269: HOLD'EM NO LIMIT ($0.50/$1.00) - 2008/09/15 1:56:45 ET
Table 'Gehrels II' 9-max Seat #4 is the button
Seat 1: ralphd27 ($101 in chips)
Seat 2: limpdug ($40.55 in chips)
Seat 3: Bohlicious ($123.20 in chips)
Seat 4: kr1kke ($123.80 in chips)
Seat 5: C.M. Burns ($54 in chips)
Seat 6: Horse1966 ($101.45 in chips)
Seat 8: commonjo ($16.05 in chips)
Seat 9: Bigstud4 ($110.40 in chips)
C.M. Burns: posts small blind $0.50
Horse1966: posts big blind $1
Monoxide123: sits out
*** HOLE CARDS ***
Dealt to Horse1966 [Qs 9h]
commonjo: calls $1
Bigstud4: folds
ralphd27: folds
limpdug: folds
Bohlicious: folds
kr1kke: folds
C.M. Burns: calls $0.50
Horse1966: checks
*** FLOP *** [5h 3h 5s]
C.M. Burns: checks
Horse1966: checks
commonjo: bets $1
C.M. Burns: folds
Horse1966: calls $1
*** TURN *** [5h 3h 5s] [Qh]
Horse1966: checks
commonjo: bets $3
Horse1966: calls $3
*** RIVER *** [5h 3h 5s Qh] [Qc]
Horse1966: checks
commonjo: checks
*** SHOW DOWN ***
Horse1966: shows [Qs 9h] (a full house, Queens full of Fives)
commonjo: mucks hand
Horse1966 collected $10.50 from pot
*** SUMMARY ***
Total pot $11 | Rake $0.50
Board [5h 3h 5s Qh Qc]
Seat 1: ralphd27 folded before Flop (didn't bet)
Seat 2: limpdug folded before Flop (didn't bet)
Seat 3: Bohlicious folded before Flop (didn't bet)
Seat 4: kr1kke (button) folded before Flop (didn't bet)
Seat 5: C.M. Burns (small blind) folded on the Flop
Seat 6: Horse1966 (big blind) showed [Qs 9h] and won ($10.50) with a full house, Queens full of Fives
Seat 8: commonjo mucked [5d Ad]
Seat 9: Bigstud4 folded before Flop (didn't bet)

How do you like my out-of-position float here? If you're ever going to do such a thing, this seems like the right situation. It's a bone dry flop. I can have a 5, but he is unlikely to. He is likely to take a stab at the flop with any two cards, since it is just him and the blinds.

I hate betting rivers in this situation because the reversal of action (leading out when previously you have been checking and calling) looks so damn strong. My theory at this point was that he had a pocket pair, and it's hard to see him calling with that. On the other hand, he's surely not going to bet it either, so maybe my best chance is to go ahead and bet and hope to get a suspicious call. Yeah, that sounds right.