Questions about Korea, China, Japan, Thailand, and Taiwan?

Wow... I would not recommend Japan if you don't know anything about Japanese culture. There are so many things you have to know about before living there. For one, it's rude to blow your nose in public. If you don't slurp noodles loudly while you're eating, you're being impolite. There are many different ways of speaking Japanese (You would have to learn some Japanese if you were to live there, right?), depending on who you're talking to. Putting soy sauce or anything else on your white rice and leaving your chopsticks in the bowl is also rude. These are just a few of the general manners people have... I would suggest picking one of the other choices.