Your Princeton Applied Research DOS-based software (M270, M398, M352, etc.) will run in a Windows^® 95/98/00/NT/XP operating system, it simply runs out of a DOS shell.  The only real issue is proper GPIB setup--making sure that you no longer have a GPIB.COM device driver in your CONFIG.SYS file if you're running the latest Windows^® GPIB card and driver (see the communications section for GPIB setup and configuration).