It depends if the users needs to be created or not.
If the users are already created, you can copy the ~/.kde from the source user to the destination user. For the menu structure, you need to copy ~/.local as far as I know.
If the users are not yet created, copy the ~/.kde and the ~/.local directories to /etc/skel. When creating a user, the files in that directory are copied to the home directory of the new user.
BTW1: .kde contains all setting of the user at that moment. That includes password and other - proberbly private - stuff.
BTW2, you shouldn't have a root desktop, because it shouldn't be neccesairy to login as root. You can use kdesu to open a specific application as root, or su - if you want root-rights in a konsole.