[MiKTeX] XeTeX in MikTeX from ProTeXt distribution with Windows XP

[Dave W. <dav...@gm...>]

I installed MikTeX using ProTeXt from the Sept 2008 TeX Collection DVD.
(Previously I had MikTeX installed from a ProTeXt CD from the TeX Collection
two or three years ago.)  The XeTeX documentation and the MikTeX
Settings/Roots window both say that there should be a font configuration
file in the :/Documents and Settings directory which says where XeTeX is
supposed to find the operating system's font files.  I find no MikTeX
directory and configuration files in Documents and Settings.  Is this a file
that is supposed to come with the MikTeX instllation or a configuration file
that I am supposed to create?  I'll greatly appreciate a pointer to
definative documentation about this; I've been searching for hours and
haven't found it yet.  Thanks, Dave