how can I force display in another language

I'm currently using a Vista computer with settings in French.

For creating help files and taking screen snapshots purposes, I need to force windows to display start menu, control panel etc... in English, and later 开发者_开发问答German, Spanish...

Of course, I can't afford to buy several computers! Is there a way to change the system language display?

Windows 7 now comes with language packs (see video)

Apparently the same is true for Vista