Pretty sure this is a big leak in my game cause I'm not sure what to do. Used to call most of these spots until one time I heard CTS mock someone derivisely for calling off his stack "just to chop". Now I'm confused.

Villian here is a bad 60/10 donk. Didn't think he was too aggro at the time the hand was played (early in the session), but as session wore on he got more and more aggro postflop.

Blinds: $2./$4.
6 players
Converter

Pre-flop: (6 players) Hero is UTG with J A
Hero raises to $14, 3 folds, SB calls, BB folds.

Flop: 5 A 2 ($32, 2 players)
SB checks, Hero bets $21, SB calls.

Turn: 3 ($74, 2 players)
SB checks, Hero bets $47, SB calls.

River: 4 ($168, 2 players)
SB bets $168
Hero?
Final pot: $168

Said donk snap check-called both streets and snap-potted river

And how does analysis change against a good player?

You can always push and I think I would have here. If he has a 6, oh well...
This is pretty much a freeroll imo. He probably won't fold but he might...

Against a donk who is passive as you thought at the time i think id fold the river.

Also, im not exactly sure with the math, but a shove might be better than a call.