How to Set Up a Document with Front Matter Numbered Separately
http://word.mvps.org/FAQs/Formatting/NumberingFrontMatter.htm

Barnhill, Suzanne
Word MVP Site, The
2002

Abstract:

Publishers call the preliminary pages in a book the 'front matter.' They aren’t always numbered separately—some books start with the title page as page 1 and are paginated continuously throughout—but when there is a significant amount of front matter, it’s conventional to number it using lowercase roman numerals.