Detect default language

[brasibrasi]

This is my problem: i don´t speak english and i don´t know how to detect the default language of the user PC.

I need to do this:
I have a CD in spanish (buttons and menus) and i need to make this buttons and menues change to the default language fiiles of the users PC (german, english, etc).
Is possible to make this with .xml or .ini files? How?

Thank you very much!
Sorry for my english (I hope someone understand what i try to explain)

[brasibrasi]

Re: Detect default language

I´m speak spanish and portuguese.
So, if the answer is in one of this languages , is much better! (in english its ok, I try to understand)
I´m speaking like an indian?

Si alguien sabe sómo realizar esto, por favor avíseme.
Gracias
Se alguém souber como fazer o que eu preciso, por favorme avise.
obrigado