NL100: Boat on the river and passive villain raises. Line check please

[AlexB182]

Villain is 8/5.5/2.25 over 250 hands. Nothing unusual but he seems to be really tight...
I run at 15/10.
I think PF and flop are standard. On the turn, I think about a 2nd barrel but villains been so tight so far that he could easily c/c with hands like AJ or maybe KJ - TJ on the flop IMO. So when he checks turn behind I start to wonder what he got and plan on checking behind or folding on the river to any bet. But then the 3rd 7 comes and, of course, I bet again. When he reraises quite small I think like WTF...
All comments welcome, would it be stupid to just call his river raise?
Would it be good to fire a 2nd bullet on the turn here?

Full Tilt Poker, $0.50/$1 NL Hold'em Cash Game, 9 Players
LegoPoker Hand History Converter

CO: $20.35
BTN: $97
SB: $97.50
BB: $103.60
UTG: $58.60
UTG+1: $231.35
UTG+2: $76.90
MP1: $175.95
Hero (MP2): $157.25

Pre-Flop: 7[img]/images/graemlins/heart.gif[/img] 7[img]/images/graemlins/spade.gif[/img] 7[img]/images/graemlins/heart.gif[/img] 7[img]/images/graemlins/spade.gif[/img] dealt to Hero (MP2)
4 folds, <font color="red">Hero raises to $4</font>, CO folds, BTN calls $4, 2 folds

Flop: ($9.50) 5[img]/images/graemlins/heart.gif[/img] 2[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/spade.gif[/img] (2 Players)
<font color="red">Hero bets $7</font>, BTN calls $7

Turn: ($23.50) J[img]/images/graemlins/club.gif[/img] (2 Players)
Hero checks, BTN checks

River: ($23.50) 7[img]/images/graemlins/diamond.gif[/img] (2 Players)
<font color="red">Hero bets $14</font>, <font color="red">BTN raises to $40</font>, Hero ?