If I have this on Wii VC and it is still on my old Wii, then I download this 30cent version to my Wii U, and then after that I transfer all of my contents from my Wii to my U, what will happen?
Will I have two versions of Super Metriod playable on the U? I don't want any conflicts, and I want to download SM tomorrow for 30cents, and then a month from now I'll transfer over all contents from Old Wii to New U (transferring next month due to moving...)
You're safe. Wii Mode is separate from the Wii U's main menu, so you'll keep your Wii copy in addition to the U one.