I currently have up and running, on the same computer and operating system:Might and Magic 1,2,3,4,5,6,7,8,and 9
Heroes of Might and Magic 1,2,3,and 4 (Heroes2 POL expansion)
Crusaders of Might and Magic
Heroes Chronicles; Warlords of the Wasteland, Masters of the Elements, Clash of the Dragons, and Conquesr of the Underworld. (The only Chronicles I don't have is "The Final Chapter" - I could never find it).
All programs are UNPATCHED, with the exception of MM7 which required MOK's patch to run. I intend to apply the 1.1, 1.2, and 1.3a patches to MM9 as soon as I download them.
This proves, I think that all MM's can be run successfully under WINXP SP2 on a Pentium 4 machine (although a rather slow one by today's standards, 1.7GHz)