MORE FUN!!!

You don't have to have the wheel. It
just makes it more comfortable and
realistic. I don't think you would be disappointed.

I love the wheel. It makes it easier to control your movements and make them more "car like." I've already purchased a second wheel so that my husband could use one too.

Yes each person needs their own wheel

Each person would need a controller if you are playing two player, but it is not necessary to have a wheel. We find it easier to have wheels, but not necessary; although we do play with the wheels!

if you are playing at the same time yeah you do

The short answer to your question is yes, you can use the wheel for any other game you want. If you are playing another racing game that uses motion controls similar to Mario Kart, then yes you can use it. The wheel doesn't actually change the functionality of the remote, it is really just there for looks. You can play Mario Kart with just the remote and it will play exactly the same.

I haven't personally tried it but apparently there is a provision for playing online via the Nintendo WFC 2 player.

According to the manual, 2 players using 1 Wii can play against opponents or with friends regionally or around the world.

any racing game that requires you to drive by holding the wii remote sideways to steer can use the wii wheel.