Thanks guys,
as I do have an XP64 Disk I followed Mark's instructions, which did the business.
My problem with 'Virtual' XPs was that they all generate their own C: drive, from which it is impossible to access other drives on my system, which meant that not only could I not read from or write to my data drive, I couldn't load the license file for my CAD program. That, and the fact that I'm having a problem getting Linux to 'see' the parallel port, where my dongle resides, means I think I'm going to have to settle for a dual boot option for now.
Thanks again for your help.
Tony N