Question on MUI Interface

If I want to install a language pack on vista, is the base OS still the
english version or has
this changed in vista?

Thanks
Christian Schindler

My understanding from what I've read here is that VISTA is "language
free" -- ie all the language is in the files you can download and
install.

But -- you can only change languages with VISTA Ultimate and I gather
it is not absolutely perfect. I've read of people with Chinese or
Japanese machines who have changed the language module but get some
error messages in the original language.

Also the language change is not automatically applied to your
applications -- but may be if they have been written to suit this new
system.