It's difficult to make a list of favourite games ... but here's my effort:
1 - Super Mario Galaxy 2 ; It's simply my favourite game this generation (and yes I have other consoles as well). Platforming perfection as far as I'm concerned.
2 - Xenoblade Chronicles ; Nintendo has really pissed me of sometimes when they decided not to release a game in Europe, but with the Wii things got much better (I'd still love to have ExciteBots and Super Mario Sluggers though). I still can't believe they released this gem...
3 - Donkey Kong Country Returns
4 - Wii Sports Resort
5 - The Legend Of Zelda : Skyward Sword
6 - Tatsunoko vs. Capcom : Ultimate All-Stars
7 - Sin And Punishment : Successor Of The Skies
8 - Naruto : Clash Of Ninja Revolution
9 - The Last Story
10 - Kirby's Adventure Wii ; it's really difficult to choose between this and Epic Yarn but I played this one quite a bit more than Kirby's excellent first Wii game so...
Honorable mentions:
The House o/t Dead : Overkill, Zack & Wiki : Quest For Barbados' Treasure, Excite Truck, Little King's Story, Mario Kart Wii, Monster Hunter Tri, Muramasa : The Demon Blade, Rune Factory Frontier, Sonic Colours, Super Smash Bros Brawl & World Of Goo.