MUI ( Multi-Language User Interface ) Pack for VISTA ULTIMATE

I would like to know how to update and use the MUI ( Multi Language User Interface ) pack for VISTA ULTIMATE 32 bit?

I live and work in Japan so my Vista is Japanese Edition but my Japanese has not been enough to really understand the whole Vista features and also I NEVER use Vista, so both the OS and the language are new for me.

I need to change the language to ENGLISH.

Thank you very much.