Initially I was raising hoping to play for set value, after the flop was checked around I figured a stab at the pot was worth it with outs to a straight or trips still a possibility. Thoughts?

I probably should have check/folded the river.

PokerStars No-Limit Hold'em, $0.25 BB (6 handed) from (Format: FlopTurnRiver)

MP ($16.45)
CO ($12.75)
Button ($34.80)
SB ($17.75)
BB ($29.80)
Hero ($22.85)

Preflop: Hero is UTG with 4, 4.
Hero raises to $1, MP calls $1, CO calls $1, 2 folds, BB calls $0.75.

Flop: ($4.10) 6, Q, 5 (4 players)
BB checks, Hero checks, MP checks, CO checks.

Turn: ($4.10) 7 (4 players)
BB checks, Hero bets $3, MP folds, CO calls $3, BB folds.

River: ($10.10) 2 (2 players)
Hero bets $1, CO calls $1.

Final Pot: $12.10

Results in white below:
Hero has 4s 4h (one pair, fours).
CO has 7d Ad (one pair, sevens).
Outcome: CO wins $12.10.

Raise is fine, but I would raise to 1.50, that way you get less calls. With so many people in, I don't mind checking the flop, but a continuation bet here is normal(especially on such a nice flop)...even with Ace high or less. I would much rather bet the flop than the turn, mainly because people will call you down weak(like A7 did) after you check the flop. That river bet is spewage, do not make it. Give up and don't put any more money in the pot on the river.

I agree totally with the river bet.

I tend not to make cbets from early position with a low pocket pair if there are that many players in the hand, usually its a case of "set or forget".

PFR is fine. But make a CB! It's okay to check here, but this is a pretty soft board and a CB is a good idea. Generally speaking, if you PFR oop, get called in multiple spots, check the flop, THEN fire the turn, you're going to get called VERY light.

That was probably the worst river bet I've ever seen...Either make it 8 and a real decision for villian, or check-fold.

i think one of the key issues here is what danhdan mentioned about sizing your pfr. i think different tables have different sweet spots, and you need to figure out what it takes to get it HU or (maybe) 3-way and raise that amount. it's possible that you just ran into three other decent hands, but if A7s is calling your 4bb pfr, you need to make a little more effort to put the fear of god into him.