In review:
DOS/MSDOS: Stable, quick, fairly simple once you learn the commands, but difficult to multitask in. If something crashes, it just shuts down and you get the prompt again.
Windows 3.1: Stable, easy to use, relatively fast, decent multitask ability, shit-poor crash recovery.
Windows 95: Shaky, bloated, crash prone, better multitasking, piss-poor backwards compatability with 3.1 and DOS programs.
Windows 98: More shaky and bloated, crashes at the drop of a hat, similar multitasking to 95, slightly faster on some systems than 95, but still just as poor with backwards compatability.
Windows 98 SE: See previous OS, but reduce crash percentage by about half.
Windows NT: Almost have to TRY to crash it, solid, stable, fast, and efficient (compared to other windows versions). Incredibly poor backwards compatability. Not truly meant for home users.
Windows ME: Makes Windows 95 look like Linux, has a "system recovery" feature that crashes just about as often as the OS itself. Still based on the 9x/DOS core, so it's more backwards compatable than NT.
Windows 2000: Similarly to NT, very difficult to crash through normal usage (though, viruses are more prevalent for this flavor).
Windows XP (Home or Pro): Finally, a system that doesn't crash too often (comparable to NT), has relatively decent backwards compatability (I've run old DOS games on it), works fast on newer systems, actually optimizing performance for many. Multitasking is a bit more organized than other Windows systems. System Recovery has been made into something USEFUL (though some viruses now attack the System Recovery files themselves, making it almost too dangerous to use!)
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Linux: Older versions were command-line based, impossible for most home users, newer versions are nearly user-friendly. Installs are a bitch at times, and compatability issues abound when it comes to hardware. Hope you don't have a winmodem. Comes in many different flavors, including the most user-friendly, Red Had and Mandrake.
Solaris/Sun: Haven't really touched them, so I couldn't tell you.
MacOS9: First flavor of Mac I tried. Couldn't get used to the filestructure or the single-button. Also, throwing a CD into the trash bin isn't very intuitive, in my opinion.
Mac OSX: Faster, prettier, and more stable, plus I've seen many OSX systems with two or more button mice. Finally! As for what makes it better, it's more stable, being based on FreeBSD. For photoshoppers and video editors, I've heard that the colors are more "true" on Macs. I've never noticed a difference, but I guess I can understand this possibility. That STUPID bar at the bottom of the screen makes my head hurt. Uses a seperate graphic processor to make it's neato effects. yay. Lack of common games, applications, and other programs makes it less useful to most people, but the ones that have been ported or created for macs are really well-done. Note for Warez Pups: You ain't gonna find it on a Mac, don't even bother looking.
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All in all, those are my opinions of operating systems I've tried out, or worked with for a long time. Obviously, my Windows views are far more detailed, as I've had very little time working with the other systems. Linux frustrated me, and proved to be ultimately worthless for me. The Gimp is nowhere near Photoshop, there is no Trillian (and the programs similar on Linux are far less full-featured), I had problems with drivers and whatnot, and all the open-source stuff in general showed it's non-funded roots.
I have had very little experience with macs, but that little experience turned me off them. Yeah, I like a bit of pretty in my workspace, but I don't like a lot of hassle learning how to use fifty new toolbars that run away from my pointer, and I never liked throwing things away, so tossing the CD in the trash just bugs me. How about a simple "right-click, unmount", or like Windows does, press the button, and watch the CD come out!
I also can't stand Linux/FreeBSD/Mac/Whatever fanatics trying to get me to use their operating system. Windows crashes once in a while, I accept that. It's prone to viruses, I accept that and put a lot of caution towards my usual tasks. Sure it's a hassle, but so is mounting and unmounting drives, booting out of the GUI to install shit, and reading entire books just to figure out how to change the goddamn resolution and play CDs.
IT Pros: You stay with your *nix flavor. Bully for you.
Graphics, Photo, and Movie experts: You've got your mac, now leave me the fuck alone. I LIKE using PS7 on my Windows box, K?
Office and Home users: It's more expensive than free (linux), but cheaper than buying dedicated hardware that is overpriced (mac), so why not just stick with Windows? It sucks sometimes, but so does life.