When dealing with hardware that existed for basically one OS generation, drivers are going to be crazy specific. Already made an image of the drive on the Oce for backup sake and will probably convert it to a solid-state HDD for reliability sake. At best, an OS 'upgrade' might be shoe-horning
Windows Vista on the thing at a huge hit to reliability (and one could argue that it would be a downgrade). Getting 64-bit drivers would basically be impossible, so would kneecap you on any current OS. Embedded systems be like that.
I am definitely going to scope out the system interface where it talks to the printer. The Scitex printers were fascinating, but the OS seemed to be somewhat custom.
If using an old vinyl cutter or something that just speaks HPGL over a serial connection, the operating system is almost a non-issue as long as you can generate the code and stream it to the port.