Free Realms, the mostly free MMO from Sony, opens today (the website is currently under maintenance in preparation). It’s a game for all ages, and is laden with minigames, pets, PvP, cardgames, and all that. People who have played it seem to love it and find plenty of things to do.
Check out the trailer for it below:
Similarly, take a gander at Wizard101, another MMO for all ages.