mismatch in the regions means the region of the game is not the region of your conole. For you just set it in the options to force NTSC-U for whatever game you are playing.
If you want to do it disc bound you will have to search out whatever game you are looking to get on wiimmfi to play.
Like playing with disc and launching cheats on wiimmfi with smash bros. game.
http://smashboards.com/threads/guid...ccasional-server-issues-are-temporary.355374/ You will need the proper .gct and whatever else to patch the disc to load to a different server. Pretty easy huh? Depending on the game you are playing someone with a usb gecko may be able to dump the mem to help with building the proper codes to allow this. (or you go see the God like user Happy Bunny right here on GBAtemp and buy one of those new breed geckos)
Anyway hope some of this helps you somehow.