Speech Recognition System - Customization

I'm pretty sure a lot of you guys watched the movie Iron Man (2008) or Iron Man 2.

Iron Man has like this super computer interface system that monitors his suit, home, life, work. Pretty much a life assistant.

What I want is to change the voice in my Speech Recognition System to that British accent J.A.R.V.I.S. (Iron Man's super computer) had in the movie.

Moreover, When I say " Open notepad". I want the computer to open notepad and reply by saying "Opening notepad".

Is that possible in any way or means?
And if not, is there a J.A.R.V.I.S. like software?

I hope this may work for you found this:

To do this:
1. On your Windows Phone, flick left and tap Settings.
2. Scroll down and tap Region & Language.
3. Tap Region Format.
4. Choose desired language, there should be options for English (United States) and English (Canada).

Well thanks for that mate, but I was talking PC wise, Windows 7 to be more specific.