The thing with floating is, you can only do it so often. They will notice it, and just fire a second barrel against you on the turn if they think you're floating.

2nd hand - I don't understand why you don't just raise him all-in on the flop.
(don't post results, please. It really messes with my head)

Hand 3 - board is extremely draw heavy. Bet more on the flop. Turn raise is ok. Go broke on the river.

(I'll spare myself all the "IMHO" - I'm a microstakes player who never successfully played 25NL for a longer period of time... so take it for what it's worth)