You'll most likely get several responses to the effect that there have been umpty-nine other polls on this subject, so other than this sentence I won't mention that fact. Please use the search function in future though, to save unnecessary redundant polls. Also, usually the monthly polls are conducted by the site admin, and the current one each month will be found stickied at the top of this board. A name that describes the actual poll would have been a better choice for your subject.
I'm using a variety of OSes on different machines.
My main rig has XP X64 Edition on it. There are hundreds of little things I'd like to change about it, but I think that's true of everyone. I'm happy with it.
As for your second question - what do I like/dislike about newer/older versions, that's a long story, but here's a short version.
Windows 95 and 98 don't support much of my hardware and I've found them fairly unstable. Windows NT 4 is a great OS IMHO, but again it doesn't support most of my hardware. Windows 2000 is also a great OS, however I've found that on a machine with adequate memory it's actually slower than XP. XP is fine, and I would use that but for the fact that I've discovered two better OSes. Windows Server 2003, I've found that's faster than XP on the same hardware (at least for me) and is also based on a newer kernel so is more stable. Disadvantage is that some software won't run on it. Windows XP X64 edition is based on Server 2003 but is 64 bit. Compared to XP it's faster for me, compared to Server 2003 it runs more software. Vista I haven't had much experience with, ditto Windows 7, Mac OS, and Linux.
I still use, on a fairly regular basis, NT4, 98SE, 2000, XP and Server 2003, it's just that for my main machine XP X64 ticks the most boxes.
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