choosing a language for a new laptop English and Japanese

Hello,
I just bought a new laptop (ASUS K53E). I'm currently in Japan and bought laptop here. I'm stuck at the set up page where I have to choose the region and languages. I would prefer English as main language, but I'm afraid I will have problems later with Japanese keyboard, I use both English and Japanese in daily life. There are two things, language and keyboard, that I can choose the language for. And the physical keyboard is Japanese (qwerty with additional buttons).
Also can I add more languages later on? If I plan to add one more language which keyboard is best for initial set up?

Would be grateful for any tips, its a first time I bought laptop outside of Europe.

Be sure to make your Recovery Disks and preserve the Recovery partition if you reinstall so that you can revert to the state you received the computer and hopefully make these Setup choices again if needed in the future.

Otherwise languages are only interchangeable when you have Ultimate which provides all of the language packs via optional Windows Updates.

However reinstall with another language is sometimes possible depending upon the region of your license even though the license is language-specific. The choices you have now should also be available by finding an installer for that language to clean reinstall, then activate with the Product Key on COA sticker. However you may have to try it to find out for sure, so be sure to preserve your factory Recovery options and and Win7 backup image of your install after setup.