I play Neopets. I played Neopets before I started playing VMK. I can't recommend it as a replacement for VMK as it is nothing like VMK. I like to play the word and puzzle games. I like to collect stamps for my stamp album and "read" books to increase my pet's intelligence. Beyond that, I don't have much interest in actually playing the meta-game. I do have a shop but haven't bothered to replenish the stock in a while so the inventory is a bit low. I actively collect Rainbow Dung with the hope of wasting neopoints someday and creating a gallery to show off my collection. If anyone here plays Neopets, you can send your extra Rainbow Dung to i_like_green_cake. I'm serious, I want more Rainbow Dung. I have no idea why I collect useless Rainbow Dung other than I love the way it looks and because I find poop references to be funny.
I also play Phrase Phrenzy on the Game Show Network (GSN) using my daughter's account. Again, it can't even be considered to be a replacement for VMK. I wouldn't let children play on that site, the chat there is way too adult. I generally create a private parlor for playing Phrase Phrenzy and just play against two computer players. I have no desire to interact with the people I've seen taking part in the general chat.
Fly gave me a Webkinz Frog so I can start playing there too.
My son plays some games where he does some very demented things like making a flail out of humans, he seems to be learning a bit about physics in the process. I'll probably check those out too because I love doing those same kinds of demented things. I don't think he plays any family friendly games. He likes Navy Field a lot though which has piqued his interest in WWII and history in general.