Annoying sets

[friends]

Prima - 0,25/0,5

Hero - MP1 with K [img]/images/graemlins/heart.gif[/img] 10 [img]/images/graemlins/spade.gif[/img]
Preflop
2 folds, villain calls, hero checks (second BB), 4 folds, BB checks.

Flop 3 [img]/images/graemlins/spade.gif[/img] 6 [img]/images/graemlins/heart.gif[/img] K [img]/images/graemlins/diamond.gif[/img]
BB cheks, villain checks, hero bets, BB folds, villain checks

Turn 5 [img]/images/graemlins/club.gif[/img]
Hero bets, Villain Raises, Hero calls (???).

River Q [img]/images/graemlins/spade.gif[/img]
Hero checks, Villain bets, Hero calls.

Villain showed 66.

Question:
1) How to recognize these slowplayers?
2) Should I call the turn?
3) When I calculated odds thinking about drawing should I count my investment on the turn as 1BB(because it got clear that I need drawing only after raise) or as 2BB?
4) How do you play in such situations?