Here's a quick description of MUI vs Local Language versions.
The MUI can only be added to English builds of W2K. As stated above, it provides a Multilingual User Interface (including MOST dialogue boxes, icon titles and help files) but doesn't change the registry and other really low-level system bits and bobs.
A full local lnaguage version is literally that - the whole lot is localised to (say) German, French etc.
The MUI will add about 50Mb per language to the size of the installation - actually works quite well if you use RIS to roll out base workstations without too many applications on them.
RosieBsDad