I've tried these things with the kids I'm around (aged 2-7), and I was just met with frustration for all the things I tried (Doudou, Xubuntu, whatever).
As much of a nix-zealot that I am, in the end I resigned to using an iPad with several educational apps.
As much of a nix-zealot that I am, in the end I resigned to using an iPad with several educational apps.