Everything Nintendo, Zelda, Mario, Metroid, Kirby itp.
Get some of the Just Dance games, Wii isn't the best way to play them, but it has every up to 2019.
Metroid Prime Trilogy is the best to play on the Wii because of the controls.
Samba de Amigo is quite clunky on the Wii, but if you don't have Switch or the original very expensive Dreamcast version it's OK for some casual play.
Wii is very good for shotter games, both light gun, FPS and TPS. Get House of the Dead Overkill, 2 and 3, get Ghost Squad, get Resident Evil games, even Call of duty is fun with IR aiming,
Bully has a quite good port on Wii.
Driver San Francisco and Prince of Persia Forgotten Sands have completely different versions on the Wii, worth playing.
Wii Sports, Party, Play and other are must have on Wii.
Punch Out is also fun.