Windows 7: Some Programs Installing in Wrong Language

Good evening everyone~

I recently got a new laptop and have been installing all the things I want and need on it. Aside from my standard English keyboard, I also have the Japanese keyboard (Microsoft IME) installed, for this the Language for Non-Unicode Programs is set to Japan. This is so that I'm able to play Japanese games.

It's only a select few things that install in Japanese; a Roxio update installed in Japanese. Sims 3 installed fine in English, but then the expansion pack installed in Japanese. And...by in Japanese I mean in the game is fine, but the installation setup was in Japanese. Then I went to use AnyVideoConverter only to find the whole thing is in Japanese.

My Japanese isn't horrible but it isn't brilliant enough to deal with a bunch of programs in that language. So what should I do? Keep the Language Non-Unicode setting on UK, and then only change it to Japan when I really need it? Or is there another way? Is it doing it for some other reason?

Any help would be greately appreciated!