Devices from the 1. and 2. generation support at least 25 languages. At the language menu every language name is displayed in its own language and lettering regardless of the selected gui language. The following list shows this names and the english translation thereof. The Unicode codepoints are given for languages not using latin letters, and transliterations or hints for the pronouncation.
Four of them using special subset fonts for display:
汉语(简) : chinese simpl. (chinese language (simplified) - U+6C49 U+8BED (U+7B80) - hànyǔ (jiǎn))
漢語(繁) : chinese trad. (chinese language (traditional) - U+6F22 U+8A9E (U+7E41) - hànyǔ (fán))
日本語 : japanese (japanese language - U+65E5 U+672C U+8A9E - nihongo)
한글 : korean (hangul - 한글 (U+D55C U+AE00) - hangeul)
The following 21 languages are supported by one generic font, latin written languages first:
Bahasa Melayu : malay
Česky : czech
Dansk : danish
Deutsch : german
English : english
Español : spanish
Français : french
Italiano : italian
Magyar : hungarian
Nederlands : dutch
Norsk : norwegian
Polski : polish
Português : portuguese
Suomi : finnish
Svenska : swedish
Türkçe : turkish
Ελληνικά : greek (U+0395 U+03BB U+03BB U+03B7 U+03BD U+03B9 U+03BA U+03AC - eliniˈka)
Русский : russian (U+0420 U+0443 U+0441 U+0441 U+043A U+0438 U+0439 - ˈruskʲɪj)
العربية : arabic (U+0627 U+0644 U+0639 U+0631 U+0628 U+064A U+0629 - al-ʿarabiyya)
فارسی : persian (U+0641 U+0627 U+0631 U+0633 U+06CC - fārsī)
ภาษาไทย : thai (U+0E20 U+0E32 U+0E29 U+0E32 U+0E44 U+0E17 U+0E22 - pʰāːsǎː tʰāj)
2. generation devices are ready to support seven more languages, but the files containing the translated strings are empty for now:
Bahasa Indonesia: indonesia (similar to malay, some different wording)
Hrvatski : croatian
Português do Brasil : brazilian portuguese (in writing similar to portuguese)
Română : romanian
Tiếng Việt : vietnamese
български : bulgarian (U+0431 U+044A U+043B U+0433 U+0430 U+0440 U+0441 U+043A U+0438 - bălgarski)
українська : ukrainian (U+0443 U+043A U+0440 U+0430 U+0457 U+043D U+0441 U+044C U+043A U+0430 - ukrayins'ka)
Every device has a region code, for fullfilling governmental and technical regulations, matching power cable for the charger and minor differences in supplied documentation and accessories. These regions also define on most devices the video frame rates based on NTSC - 60i or PAL - 50i markets and most disturbing the subset of menu languages selectable from the config menu. There are at least four region groups with different language subsets, the J1 region (japanese domestic market) lacks the language menu and is fixed to japanese. Every other region group contains english as a selectable language and a varying subset of the other languages without(!) japanese.