I admit my ignorance when it comes to Japanese game shows, but Takeshi's Castle is among my all-time favourite shows. Beside the fact Beat Takeshi is uber-awesome I always rooted for General Lee and his feeble minions. The show was so good it received commentary in +20 languages. I liked watching it 'raw' because it didn't need explaining
I'm sure I'm missing out on some other shows that don't require understanding of the language.
Its a great show, I love it when its shown with English voice overs, I have not watched it for quite awhile, the closest thing to it on air at the moment is Wipeout.