The Wii will NOT be region free despite early reports from Nintendo of America that first party Wii titles would contain no region locks. NOA has since recanted that announcement and made it clear that the Wii will be region locked in all territories including the US.
As for titles I plan to pick up on Wii launch day, I've already pre-ordered the following titles:
Rayman Raving Rabbids
Legend of Zelda: Twilight Princess
These are 4 very strong titles judging from what I've seen while researching the Wii launch titles. I had planned on purchasing Wii Sports but now that it's a pack-in, I won't have to. : ) These 4 games plus Wii Sports should keep me busy until Super Mario Galaxy hits store shelves.
I'd have to say that the Zelda title would be a must-have at launch and Rayman Raving Rabids looks really fun, although it's not a traditional Rayman-type platformer as I was hoping it would be, rather more of a mini-game collection similar to the Mario Party titles. Check out IGN or GAMESPOT and watch some of the videos and trailers of all the launch titles to help you make up your mind.