I would highly recommend Resident Evil 4: Wii Edition. It was my first Wii game other than Wii Sports. It is phenomenal. The motion controls work very well with it.

Also, Metroid Prime 3. This game, in my opinion, probably has the best use of the motion on the system.

If you can find it, Zack and Wiki is a lot of fun. It is basically a point and click puzzle game, similar to Monkey Island.