Visiting Japan this December, needs help on etiquette, attitudes and clothing?

Question:

Questions 1-6 are meant to help a friend of mine, since I'll be visiting with her. She can't really speak Japanese, and has quite the weird accent even with English.

1. When visiting a traditional restaurant, will it be rude to sit with crossed legs and ask for spoon and fork instead of chopsticks?
2. Is it even alright to squeal (loudly) at cute goods in Akihabara/Ikebukuro? (e.g: doujinshi, cosplay items, etc.)
3. What is the basic clothing for winter in Japan?
4. Will Japanese be offended if a foreigner speaks loudly in public?
5. If you can't speak Japanese at all, and got lost in Japan, what is the most accurate thing to do? Will it be safe to ask pedestrians around?
6. Will childish attitude be tolerated for a 15-years-old?

The questions below are optional. It's just my personal curiosity. Note that I have self-taught Japanese to myself since last year.

7. Being an Indochinese with the average Asian-face, if I suddenly say:
「私は日本人じゃないので、もう一度おゆっくり話してください」?
Is it considered rude, weird or improper?

8. Do you have bad experience with foreigners in Japan?

I apologise if my English is quite weird.

英語はあまりよくないですが、リプは日本語でもおｋです！

Answer:

1. No problem.
2. If you want to, sure. You won't be kicked out of the stores or anything... maybe just some strange looks.
3. Boots, jackets, scarves.
4. Not offended, but annoyed. Even I am annoyed by it.
5. An iPhone helps. Many signs are also in English. It's pretty hard to get lost, really.
6. EDIT: You can do as you like if you're there on your own. No one will confront you, but you may get some stares. Obviously this sort of behavior isn't ideal, but if it can't be helped...
7. It's perfectly OK.
8. Most foreigners support one another in Japan, so no, not personally.