Rhythm Heaven Fever (best game on Wii no competition!!!!!)
Super Mario Galaxy 1 and 2
Donkey Kong Country Returns
Monster Hunter Tri
Kirby's Return to Dreamland, maybe Epic Yarn. They're both pretty easy (except for RtD's challenges, of which there's more in the recent Kirby anniversary thing), but at least Return to Dreamland is a Kirby game. Epic Yarn is like... a better controlling Little Big Planet, but without the level editing stuff. Speaking of easy games, there's also New Super Mario Bros. Wii.
Xenoblade Chronicles and The Last Story (both are kinda tough to emulate, last I checked)
Both No More Heroes games. Aah what a bummer that Suda51's just been involved with shit since these games.
Maybe Super Paper Mario. I liked it at the time, but it's not quite as good as The Thousand Year Door. It has a really slow start, if I remember correctly.
Sin and Punishment: Star Successor is pretty good if you're into that sort of thing. Same goes for the two Fatal Frame games (well, one is called Project Zero or something and the other is a fan translation of the fourth game).
That's probably it, I dunno. Some of those are better multiplayer, but they're all fine alone. There are more good games for the Wii, but they kinda require more players to get the most out of them (like Fortune Street). There's also a bunch of middle of the road shit that's not terrible but not really worth going out of your way to play (like A Boy and His Blob and Muramasa).
Sonic Colours is a gorgeous game and has really good music, but it doesn't stay fun for long. The levels get worse as the game progresses. Generations is a much better game, but that don't matter since it isn't a Wii game, huh!!
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