Silent Hill: Shattered Memories
Metroid Prime: Trilogy
Smash Bros Brawl
Mario Galaxy 1
Mario Galaxy 2
Resident Evil 4: Wii Edition
Kirby's Epic Yarn
New Play Control Pikmin 2
Are probably my top 10 Wii games, although I've not played Xenoblade/Little Kings Story properly yet, though I do own them. Quite a number of them are of course from other systems originally but the Wii controls really do take them to a whole other level, especially with the Prime games.
Silent Hill: Shattered Memories is an utterly fantastic game, such a shame how it was ignored by so many. Brilliantly inventive use of the Wii remote and so atmospheric. I was playing it along at the same time as Alan Wake and despite Alan Wake's superior graphics and presentation it couldn't even begin to compare to Shattered Memories for atmosphere (or gameplay
I did really like how there was such a return to 2D platformers during the Wii's lifespan as well. NSMB Wii, DKCR, Wario Land, Kirby's Epic Yarn, Return to Dreamland, A Boy and his Blob, Super Paper Mario, Sonic Colours. Some truly fantastic games.
My biggest disappointment with Wii was probably that we never received a true Paper Mario RPG game, Super Paper Mario was fun but after Thousand Year Door it was a huge disappointment.