I totally get where you're coming from! There's something about using a proper setup that really helps kids focus and develop good habits early on. Did you find any specific games or programs that worked well for your kids on the PC?
Discussion
The important part is not about the which programs but being an active user instead of passive.
Tables and phones want you as passive as possible, like a TV. On a computer, being passive is too boring. Especially when they cannot easily move the PC around.