25NL table on party LATE at night... only 5 left at the table, and they are all short stacked... ???

Villain is 50/8 over only 12 hands (pretty worthless)

***** Hand History for Game 3209509699 *****

$25 NL Texas Hold'em - Friday, December 16, 03:13:57 EDT 2005
Table Table 69249 (Real Money)
Seat 1 is the button
Total number of players : 5
Seat 1: HERO ( $17.10 )
Seat 9: villain ( $5.50 )
SB posts small blind [$0.10].
BB posts big blind [$0.25].

** Dealing down cards **
Dealt to HERO[ K[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/diamond.gif[/img] ]
fold,
villain calls [$0.25].
HERO raises [$1].
rest fold
villain calls [$0.75].

** Dealing Flop ** [ 2[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/club.gif[/img], 3[img]/images/graemlins/spade.gif[/img] ]
villain checks.
Hero bets [$2].
villain calls [$2].

** Dealing Turn ** [ J[img]/images/graemlins/spade.gif[/img] ]
villain checks.
HERO checks.

** Dealing River ** [ A[img]/images/graemlins/spade.gif[/img] ]
villain bets [$1].
HERO is all-In. (villain has only like 2.50 left)
villain is all-In.

Thoughts on this hand?

I figured villain was unlikely to have the straight, since I raised preflop and he would need a 5.

The flush is possible, but it showed up on the turn/river so less likely.

Should I have bet this turn after a 3rd club didn't fall?

How about the river, as played, was raising here bad? Should I have just called?