Windows Media Player, by default, does not come with DVD decoder (technical term is MPEG-2) built-in nor can you download for free. This is true with MP3 encoding as well; WMP cannot rip CDs to MP3 out-of-the-box. As Nick said, this has to do with the licensing and royalty issues.
However, most hardware manufactueres would bundle the MPEG-2 decoder in if their hardware includes a DVD drive. See
http://www.microsoft.com/windowsxp/e.../02april15.asp and
http://www.microsoft.com/windows/win...p/dvdplay.aspx for reference.
I still say that Fijitsu bundled it and somehow kokonutz screwed it up.