One thing that exposure has taught me is DTP is one of those areas where cross-platform issues come into play more than most types of applications. PDF does help, but sooner or later, something will pop-up.
Have a look through the Web Links for cross-platform tools and downloads.
Thanks to the KDE-Cygwin team, it is possible to run Scribus on Win2k or XP, via Cygwin. Note that this is a much older version of Scribus and is now deprecated as a native port is under way.
The most up to date info can be found on the Scribus Wiki.