I am pretty much in line with, what most people have said already:
Hand 1
You can raise a little larger pre with this stack size and especially in a freeroll. More important though is your slowplay on the flop and turn. It is a very common mistake to slowplay a set of aces, and often people do it, because they put to much weight on the fact, they block top pair.
But while this is true, that you block top pair, that does not mean, that a slowplay is the best line. People will call with a lot of other hands than just top pair especially in a freeroll. Second pair, third pair, the OESD, gutshots. And if they fold a gutshot, that is fine as well, because then you protect your hand, which is especially important in a multiway pot.
Facing the silly donk bet of 100 chips on the flop, which I call a fish bet, I would make it 500 to go, and if BB call, then I would put him all in on the turn. As played you need to put in a healthy turn bet of around 700 chips, because now the board is getting very dangerous with a lot of straight potential.
As played folding the river is fine. Any random 8X beat you now, and you are facing an overbet. The way to beat the micros and even more so
freerolls is not to be the table sherif and hope to catch someone overbet bluffing in a spot, where they can easily have value. He has that 8 here most of the time, and if not then nice bluff by him.
Hand 2
Fold pre. As played you got it in good but ran bad, so not much to analyse postflop.