From a vacuum, my standard play would be:

1st hand: fold the flop to his checkraise.

2nd Hand:
PreFlop:Why raise 3 BB? Raise 4BB. But thats just me.

Flop: Generaly fold or re-raise (75% fold, 25% re-raise). Remember, I am speaking from a vacuum. reads are very important. I don't like the call.

Turn: Reraise to Pot size, or Push. (Since you made it this far)