Hand 1 - After the J comes on the turn and I'm raised, even though it's a min raise, I have no desire to play a big pot anymore. Four-to-a-straight on the board is obvious and unless you opponent is a total moron he isn't going to raise you without at least a Q. The most likely scenario is a split pot, so I see no advantage in dumping so much money when you could be behind or your opponent also has a Q along with a flush draw and is free-rolling. After the turn raise, unless I have a good read, I try to get so showdown as cheap as possible.

Hand 2 - As was already said, after SB cold calls I would put in a larger raise. Even without a cold caller, if someone re-raises me PF and I have AA or KK when it comes back to me I pretty much always but in a raise that commits either my opponent or myself. Here I would raise to $35+ and push any flop without an A. As you played it though, you need to lead that flop. Don't be so quick to surrender control of a hand just because a scare card comes. With an A on the board you want to know where you stand immediately. If I'm called, I slow way down. If I'm raised, I dump it. You surrendered the lead in the hand and paid for it by not knowing where you stood and consequently were strung along with sucker bets.

Hand 3 - I think you played it well up until the river. That river bet is more often not a bluff than it is. It takes a lot of balls or stupidity to make that bet into someone that has been betting strong through out the hand without having something that can beat your KK. Do you think your opponent was calling those bets all along just so he could pair his J and push the river? Unless my opponent is a complete dumbass, tilting, or I have some kind of other read, I fold. Two pair, a set, a straight, a flush... it doesn't matter. They all beat you.