Ah OK I understand now... Thanks Nick. I think it's perhaps better to keep FS as it was because I can't be bothered with all this hassle. It seemed to me that the Windows and the Creative settings were working in sync because when I would change the 2/2.1 in the Creative settings to 5.1, the Windows setting would change too, from "desktop speakers" to "5.1 Surround Sound speakers", but I think the point is that I should change the Creative setting to 4.1 and the Windows one to Surround or Quadruple, right?
Still, I'll live with it. It's been a tad confusing, but we have the reached the end of this journey!

Thanks for the help.