Japanese Windows

Can someone explain to me exactly what the difference between a Japanese and UK copy of Windows is? I always thought that all Windows versions were identical, and you just changed the language or downloaded upgrades if you wanted to use a different language. I've noticed that Microsoft mention something called Multilingual User Interface. Is this something that costs extra, or is it something that can be downloaded for free? Also, is the BIOS in Japanese laptops in Japanese?

I intend to buy a Japanese laptop, because I want to learn to use the keyboard. But obviously at first, I'll be using it mainly in English. I already own a copy of Windows XP x64 Edition, so would it be worth taking that? Will the Japanese keyboard only work with a Japanese copy of Windows?

And finally, can someone tell me a good Japanese website, that I might be able to look at some prices on? Preferably one that Google won't have to much trouble translating automatically. A proper computer website preferably, like ebuyer or dabs. I assume that like the rest of the world, it's cheaper to buy a computer online from a proper computer supplier, than in a shop on the high street?

always thought that all Windows versions were identical

Yes, it is virtually the same. Except for the input method.

The main differences is that most of the prompts,icons etc appear in Japanese instead of english.

You can type Japanese with any version of windows rgardless of language version, windows XP and above have built in japanese language support, all you need to do is plug in a Japanese keyboard, or use a softkeyboard and change your regional settings.

http://www.declan-software.com/japanese_ime/

Or you can do what I did, buy Japanese keyboard stickers (I know you can find them on Amazon) and then enable the Language bar and change the keyboard settings to Japanese...

Can someone explain to me exactly what the difference between a
Japanese and UK copy of Windows is?

The main difference is the language of user interface (ie menus and
icons), online helps and paper manuals.

I always thought that all Windows versions were identical, and you
just changed the language or downloaded upgrades if you wanted to use a
different language.

BASICALLY identical; you can add Japanese IME and fonts to your English
Windows and should be able to handle Japanese flawlessly.

But note that you can't switch user interface language. If you buy a
Japanese Windows you can't switch menus/icons from Japanese to
English (or any other language).

I've noticed that Microsoft mention something called Multilingual
User Interface. Is this something that costs extra, or is it something
that can be downloaded for free?

MUI is a special add-on to English Windows and allows you to switch user
interface language, but it is provided only via corporate license or
Microsoft Developer Network. Few individual users use it.

Also, is the BIOS in Japanese laptops in Japanese?

Some are in Japanese, others are in English.

I intend to buy a Japanese laptop, because I want to learn to use
the keyboard. But obviously at first, I'll be using it mainly in English.
I already own a copy of Windows XP x64 Edition, so would it be worth
taking that? Will the Japanese keyboard only work with a Japanese copy
of Windows?

You don't need a Japanese keyboard to type Japanese. US English keyboard
is fully supported by Japanese IME.

I recommend you to simply buy an English laptop with English keyboard
and Windows and download Japanese IME to type Japanese.