Hand 1:
villain is 39/11/1.29/100. I have no reads on him.
I included results because it shows my whole play. River is easy on this board and as played, but the decision is likely on the flop (maybe turn).

I see myself playing these flops passive quite a bit, which could be a leak. I'll show my reasoning in the first comment.
Is calling flop ever good? With what hands and whats the turn plan?

Party Poker No-Limit Hold'em, $0.25 BB (6 handed)

BB ($25)
Hero ($80.28)
MP ($24.63)
CO ($27.95)
Button ($24.18)
SB ($8.53)

Preflop: Hero is UTG with K,A.
Hero raises to $1, MP calls $1, 4 folds.

Flop: ($2.35) J,A,9 (2 players)
Hero bets $2.15, MP raises to $4.3, Hero calls $2.15.

Turn: ($10.95) 8 (2 players)
Hero checks, MP bets $5, Hero calls $5.

River: ($20.95) 6(2 players)
Hero checks, MP calls $24.63 (All-In), Hero folds.

Final Pot: $45.58


Hand 2:
Villain is a complete unknown.
I bet river because I expect villain to have a worse 8 a lot and calling it.
I doubt he has a 2, 56 is possible and hmm maybe 34 or a set, but I still find it hard to give him a range. Any thoughts on his range?

Party Poker No-Limit Hold'em, $0.25 BB (6 handed)

CO ($4.65)
Button ($25.67)
SB ($25.04)
Hero ($25.82)
UTG ($24.45)
MP ($28.95)

Preflop: Hero is BB with ,.
3 folds, Button calls $0.25, 1 fold, Hero checks.

Flop: ($0.72) ,, (2 players)
Hero bets $0.5, Button calls $0.50.

Turn: ($1.72) (2 players)
Hero bets $1.1, Button calls $1.10.

River: ($3.92) (2 players)
Hero bets $2.7, Button raises to $8