[FoxwoodsFiend]

Only relevant opponent is a pretty tight, solid player. He has around $450 and I have him covered.
2/4 No Limit
Hero is SB w/4 [img]/images/graemlins/heart.gif[/img] 6 [img]/images/graemlins/heart.gif[/img]
4 limpers, Hero completes, BB checks.
Flop: 2 [img]/images/graemlins/diamond.gif[/img] 3 [img]/images/graemlins/spade.gif[/img] 5 [img]/images/graemlins/diamond.gif[/img]
Hero checks, BB bets $10, 3 folds, Villain raises to 30, Hero raises to 135, BB folds. Villain thinks for a good 20 seconds and calls.
Turn: 5 [img]/images/graemlins/spade.gif[/img]
I check, he bets $100.
So my thinking is on the flop he either had a set or a flush draw...it seems like a pretty routine fold here...does anybody call here? If so, what do you do on the river depending on if a diamond comes? Also, should I block bet the turn to give him a chance to define his hand?