[WordWhiz]

1) Raise preflop
2) Actually, now that I look at it, the preflop part is messed up. If UTG raised, then SB should 3 bet and UTG cap, so I'm not sure what's going on. I'll assume it got capped since there's 13 sb on the flop.
3) Flop raise with overpair and gutshot is good.
4) Call down after that. You're probably behind to AA-QQ, but if SB is uber-aggressive as you say, he might just be betting AK, AQ, or even AT, especially since you showed no strength preflop.
5) Can't believe you're asking for advice on the river--this is by far the easiest street. You're not seriously thinking of folding an overpair for 1 bet in a 13BB pot, are you? You only need to be good like 7% of the time.