haven't read other posts yet.. but I'd say..

1) Check, because he's 25/2 so he's not raising many hands. He can definitely have a reasonable Q that you won't be able to take him off of.

2) Bet, a flush draw is more likely than getting called with a gutshot on the flop

3) bet, he's a fish (according to PF stats)

4) check, unless I have a read that villain calls cont bet loosely but folds to second barrels