I would fold both. People aren't bluffing on the river at NL$25 when you show this much strength. I would confidently lay down my aces here.

In the second hand he either has a big draw(Ahxh/4h6h/KhQh/56/etc.) or already has you beaten, in which case folding is the best play. The only hand you beat that may play like this is a badly played 66 which IMO is the least likely. I think your betsize on the flop is fine btw, though I like $1.25 preflop after a limper.