This game is simple, and it's fun for both kids and adults. All you have to do is lay out the plastic mat with colored circles on it and have someone agree to be the spinner. You don't even need the mat, actually. You can always draw circles outside with chalk or use pieces of colored paper.
The spinner flicks an arrow so that it points to a section that reads a color and the word "hand" or "foot." You just move said appendage to said color. The first one to fall loses.
The mat is only big enough for four players, but you can use multiple mats for more players, or one of my earlier suggestions. You don't need to read to enjoy the game, so it is great for younger children. It's a good active game that will get them off the couch.
I've had a lot of fun playing Twister over the years. It does take a certain degree of coordination to win though, which I don't really have, unfortunately. Even after I lose though, it's still fun to watch the other players fall all over each other as they try to move their hands and feet. In that way, there is no way to really lose this game. I like that about it.