The FIOS fiber optic television system is the best possible way to play video games online. Small children will love it!
Usually I would never recommend video games for children this young but the new Nintendo Wii has some fun, non-violent and simple games that kids that age may love.
The selling point for the system is that the controller uses motion to mimic what is on screen.
That is to say if the game is golf, you use a small controller and "swing" it like a golf club to make the cartoon character on screen do the same.
A child could burn lots of calories and develop critical hand-eye coordination skills playing these games.
Talk to some other parents about the Wii to get more well rounded opinions, though.