Re:Some minor comments: (Score 2, Interesting)

I dunno that I'd call Windows 3.0 an OS; didn't you still have to load EMS or XMS drivers from the DOS config.sys? Anyway, Windows 4.0 (aka 95) definitely was an OS in it's own right. But Netware, also, requires DOS to boot the computer, and Netware loads from DOS. So I'd go ahead and list Windows 3.0 with Windows 4.0, rather than just considering it a shell for DOS. My list is:

1. MS-DOS 3.x - 6.22
2. Windows 3.0 - 4.1 *
3. Windows NT 3.5 - 5.1 **
4. Linux 2.0 - 2.4
5. BeOS 4 - 5
6. HP-UX ??
7. Solaris 2.6 - 9
8. Netware 3.1 - 6
9. IRIX 5.3 - 6.5
10. FreeBSD 3.x - 5.x
11. QNX ??
12. VAX ??
13. MacOS ?? - 9 ***
14. OS X 10.0 ***

Notes:
* Windows 95 was version 4.0, and Windows 98 was version 4.1. Run the command "ver" from a command prompt to see.
** Windows 2000 is Windows NT 5.0, and Windows XP is version 5.1. Again, run "ver" from a command prompt to get the real story.
*** I don't know jack about Macs, but I've used a few from the LC on up, but I dunno all the versions I've used, except a friend who let me play on his iBook running MacOS X 10.0. And since OS X was a radical shift from OS 9, I made it a different OS.

Do handhelds and calculators count?
--
PalmOS ??
HP-48G ??
TI-85 ??