It's line-up so far might not be so hot, but it will improve and I think with a quickness....not to mention they could have a lot of fun just using the Wii with their old games. I think just seeing how the new controllers work with old games could be fun for them.
Just to be sure your expectations are set correctly here, you can't use the Wii controller to play GC games. You have to use either a GC controller or the "classic" controller (which looks awful, but I haven't touched it, so take that with a huge grain of salt).