Played on an app, so no nice hand history. 7 handed 1/2 game (low rake). Most stacks between $150-$400. Very loose passive game, almost no 3-betting, most flops 4+ way.

We're in the HJ (stack $326) with AJ65.

Preflop:
UTG ($423) limps (pretty straightforward/not very tricky)
LJ (~50/30/5) ($140) pots to $9
We call
BB ($223) and UTG both call, 4 handed to the flop

Flop: J74 (Pot $37)

Checked to us, we pot, just UTG calls.

Turn: 5 (Pot $111, effective stacks left $280)

UTG checks, we check.

River: 4

UTG bets $55, action to us.

How did we do so far, and what do we like on the river? Folding, calling, or raising all seem like viable options.

Fold pre. This is a very weak hand. In Omaha you want four cards working together; you do not have this here. You'll note it is a raised pot, which raises the requirements for you to enter significantly.

On the flop you should check behind. Your holding is still mediocre. You have four outs to the nuts, and TPTK. As the player you are acting after had the initiative the first two guys could easily be trying for a check raise (although this would probably be poor strategy in a four way pot, the best play with a monster would be to just lead out for pot unless the other players were overly aggressive). Your chances of taking it down are slim, but you do have some reasonable turns. You can make the nut straight, or top two or trips top kicker. You are in position, so can be sure to see your draw, such as it is.

Fold river.

Fold pre, even without a limper this is likely a bad open.

As played, i would continue betting the turn, your hand has improved and its fairly unlikely your opponent has a straight.

Villain is mostly repping trips or overpair with river bet, its hard for you to rep a boat as most sets would keep betting turn so folding is fine. But you could take a shot with bluff-shove against some villains here and blocking the best full houses.

Meh

Fold preflop

If you are going to be bet the flop, which you probably shouldn't, I would bet smaller and not bloat the pot.

Bet turn, your hand has improved and the straight that hit is gappy so unlikely an UTG player holds these cards.

Can't raise river as it really doesn't make a lot of sense with the line you took so I would fold. If you bet turn then I would raise river.

Preflop is close given conditions described by OP. But I think on balance we need to be otb to be playing a hand this weak.

Flop is a fine bet. The fact that we only have 4 nut outs is a reason to bet, not to check, as we should be folding out plenty of 9T combos. We also often have the best hand and the best equity, especially when checked to.

Turn is a bet again. We're unlikely to be able to get value from this hand on the river unless we improve, and given the action so far we likely still have the best hand or have improved to the best hand, and if behind have up to 13 outs to catch up. If he check-raises we have an easy fold given we at that likely have only 2 or 4 outs to win.

River is close for me, call is ok, fold is probably best though