How to change a PC's language?

[Norway]

Recently I tried installing Vista on my old XP laptop, using the Vista CD which was included when I bought my desktop in August. I currently live in Sweden and that's where my desktop was bought, so that Vista is the Swedish version. Norwegian and Swedish are extremely similar (like American English vs. British English) so that wasn't a problem

However: During the installation I get the message that Vista can't be installed because it's in another language (it's in Swedish, my laptop's language is Norwegian). I'll probably have to make the language of the PC Swedish as well.

How can I do that?

[bigBonehead]

The Vista Install CD included with your desktop is tied to the motherboard ID# in said desktop, and would not be able to be Registered with MS for the laptop...