25NL 2 pair facing river shove

Villian is unkown, just sat down a couple of hands ago. Call or fold vs. unknown? I checked the river hoping to get a bluff from a missed flush draw, but thats a big bet for a bluff. Should I just lead the river with 2 pair? Also, how were the other streets played?

PokerStars No-Limit Hold'em, $0.25 BB (8 handed) - Poker-Stars Converter Tool from FlopTurnRiver.com

UTG ($56.55)
Hero (UTG+1) ($25)
MP1 ($5)
MP2 ($25)
CO ($41.65)
Button ($26.05)
SB ($10.10)
BB ($5)

Preflop: Hero is UTG+1 with Ahttp://www.flopturnriver.com/phpBB2/...es/diamond.gif, Jhttp://www.flopturnriver.com/phpBB2/...miles/club.gif
1 fold, Hero bets $1, 3 folds, Button calls $1, 2 folds

Flop: ($2.35) Ahttp://www.flopturnriver.com/phpBB2/...iles/spade.gif, Qhttp://www.flopturnriver.com/phpBB2/...iles/spade.gif, 3http://www.flopturnriver.com/phpBB2/...iles/spade.gif (2 players)
Hero bets $1.75, Button calls $1.75

Turn: ($5.85) 9http://www.flopturnriver.com/phpBB2/...miles/club.gif (2 players)
Hero bets $4.25, Button calls $4.25

River: ($14.35) Jhttp://www.flopturnriver.com/phpBB2/...es/diamond.gif (2 players)
Hero checks, Button bets $19.05 (All-In)

I feel like we shouldn't be too concerned about bet size - with his remaining stack size, it makes a shove a pretty big portion of his river bet sizing.

Your bet sizing is pretty much fine, though as a matter of preference I may have gone for $2 on the flop because he's calling with his bare flush draws, QxKs / KsTx kinda hands and aces anyway. If he calls, that makes the pot $6.35 on the turn, where you can bet $5.25 which if called gives a river pot size of $16.85 and takes the edge off a pot size shove ($16 remaining). But no biggy. I think a big part of betting bigger here though is knowing this is the kind of board you get called down on a lot, so you can extract a lot of value the times the board doesn't throw up another spade.

When you check the river, he shoves, and I'd be more concerned by a more obvious value bet by villain (half pot kinda bets). As is, there's a lot of aces and missed flush draws in his range here imo so I like a call. Obv shoving river is an option too, but at least this way you're giving villain opportunity to hang themselves.