Yes, play money won't teach you much about real-life play, but you see a lot of hands for free. You get a feel for how often you'll make a hand, flop a pair/set... You should be able to easily make a couple of buy-ins per hour in a play-money game. Freerolls are a good idea too.

I saw the thread where you posted your hands.
I should have added "don't post coolers" AA vs KK is a no-brainer. If you fold KK or even QQ pre-flop at 2NL you are giving away perfectly good money.
Post hands where you weren't sure if you made the right play. This includes hands you won.