Evening Star, see here:
Apple - Support - Discussions - Boot Camp Installation of XP freezes in ...
It is a simple fix, i had the same problem then thought it through.
make sure you are ready to install windows after you do this.
Go to System Preferences - Keyboard And Mouse.
Then it says, 'Use the F1-F12 Keys to control software features' etc
Click the box next to that then do the set up.
make sure you uncheck that after the set up because while that is checked you will not be able to use the volume,brightness or keyboard brightness.