Show me your slick

[dux]

1/2 online, passive at the moment, but as usual the players are not as bad as one would like.

I get dealt K[img]/forums/images/icons/diamond.gif[/img] Q[img]/forums/images/icons/club.gif[/img] in UTG + 2, one EP limper, I limp, MP limps, the player to his left raises, late position flat calls - the big-blind and everybody else who called once calls again. 5 players.

Flop: Q[img]/forums/images/icons/diamond.gif[/img] 8[img]/forums/images/icons/diamond.gif[/img] 4[img]/forums/images/icons/spade.gif[/img]

I find KQo questionable, but this is its flop, and there is a good chance I'm winning. But do I check or check-raise? Or is this one of those times when I check-call to keep him betting an AK AJ and worse, so I gain more money of him bluffing his way out, while saving myself money if he has AQ or better? With 4 opponents, and with a hand that does not want to give a free card, I don't think this is the case.
I decide to bet - MP raiser calls, and LP who flat called two bets before the flop, calls again. The rest fold.

Turn: A[img]/forums/images/icons/heart.gif[/img] (Q[img]/forums/images/icons/diamond.gif[/img] 8[img]/forums/images/icons/diamond.gif[/img] 4[img]/forums/images/icons/spade.gif[/img])

Not good at all. Check or bet? I figure if I choose to continue I should bet, but I don't. I check. The preflop raiser bets, late position folds, and I call. A check-call here is wrong, right? But now I'm committed.

River: 6[img]/forums/images/icons/diamond.gif[/img] (A[img]/forums/images/icons/heart.gif[/img]) (Q[img]/forums/images/icons/diamond.gif[/img] 8[img]/forums/images/icons/diamond.gif[/img] 4[img]/forums/images/icons/spade.gif[/img])

I check, he bets, I call.

Firstly, on the flop I think I have two options, to bet the flop or check-raise it. Am I correct and if so which would you do (or morelikely what % of the time would you make a certain move)?
Once the bullet falls on the turn, am I correct the two options are to bet and fold to a raise, or check-fold?
I just check-called and said "show me your slick", hoping he was bluffing, and I would have dropped it had the cold caller called again.

And lastly, do you think I won?

All comments appreciated.