Haha, okay...that is a tall order, in a year. Learn Japanese? First you'll have to learn the kanji and katakana and hiragana and whatever they all are...before you can ever start learning the words. Oh man, it sounds like a tall order. English to Japanese doesn't seem like a very natural transition. Isn't Japanese a somewhat tonal language? And the way they use the same words/syllables over and over with all different meanings...the idea is intimidating.

As for weight...why you gotta lose a ton more? You're an average size atm, aren't you? Are you going to do something that requires you to be thin?

Even if you don't do either of those things I'm sure you'd have a LOAD of fun going over there. :)