Download any gamecube iso, make sure it's in a folder and inside that folder name it game.iso. Put the folder and game.iso which is inside the folder in games (make games folder on sd card) load Nintendont through vWii, change settings you want, then make sure you load the game. (if you don't load the game the changes won't save)
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I forgot there's an easier way. Load TeconMoon's Wii VC injector, click Nintendont sd card menu, check WiiU widescreen, then Generate nincfg.bin to sd card. It should save the settings for you that way.