OTB is playing lots of pots and hitting flop after flop after flop, Villain has been there for 2 orbits and seems like the usual bad $25 player - too many pots, calls too much, weak hands shown down etc.

I have $31.15, OTB has $102.89, Villain has $19.16.

Dealing to Hero

Hero raises to $1.25, 2 folds, Button calls $1.25, Villain calls $1.25, BB folds.

Dealing Flop (pot $4)

Villain checks, simgrimes bets $4, Button folds, Villain calls

Dealing Turn (pot $12)

Villain checks, Hero bets $7.50, Villain calls $7.50

Dealing River (pot $27)

Villain checks and has $6.41 behind.

Hero checks behind or pushes? Should Hero check behind on the turn? Any other advice (apart from "Raise more pre-flop" )?

Easiest, shove, ever!

This is a definate shove here.

You can tell as soon as he checked the river card that he had nothing.

First off, the flop is 10-7-10. usually people who flop a set on a board like that, are not going to be making pot size bets, they will be slow playing as they can be sure they are in front and will try and suck others into the pot.

Secondly, he is continualy betting the pot, he doesn't check even though you raised pre-flop. If he had half a brain in his head then he would realise that you raised pre, and are calling his bets, so you obviously have some kind of hand.

Usually in this hand I would think for a bit then call if he had pushed all-in on the river. But because he checked after betting the flop and turn, then it shows he has nothing.

I feel 100% certain that you had him covered. If he had trips, then there is no way he would check the river, when you called all his bets on a board of 10-7-10-J-5.

Now lets say for instant that he isn't bluffing, and doesn't have trips but has 89.

Then the check on the river would make a little sence, you raise pre, and call all his bets down to the river, if i was in his position, i would probably check also with 89 or possibly put a small $1 on the river to see what your reaction would be, even though i turned a straight, with you insta-calling then there is a small possibility that you have made trips into a FH.

lol tl;dr

you have aces. pot is $27 and donkey has $6.50?

i would drop down and go read books and stuff if you considered folding this, no offense intended.