Glad to be of help.
Also, if you are running Unicode compatible programs, their menu selections will change to the selected language automatically which is really cool.
Not quite. A program has to have been localised first for it to change. In your language options you rank the prefered languages.
So, for me for instance, I have the languages listed:
Español, Português do Brasil, Português da Portugal, English, Italian, French, German
If a program has a Spanish localisation, it will run in Spanish. If not, then OS X checks and sees if it has a Portuguese localisation, and if so, it will use it (and will prefer a Brasilian one to a Continental one). Barring that it will normally run in English, but if for some weird reason there's no English version, it will run in Italian (which I can parse through rather well), or French (more difficult) and lastly German (which I know very little of). If none of those are present, it runs in the default developmental language (eg, the language that it was produced in).