Back in the old days.......
I have been building PCs for family and friends (and work) since Win95 was KING, in that time nearly every OS has been tried (except Vista).
My personal experience has been :-
Win98 - an Improvement.
98SE - ditto
ME - SE with some interesting new features, but lack of driver support.
XP - A little buggy at first, but head and shoulders above the rest, even if the underlying code still allows exes originally written for Win3.1 !!
7 - M$ attempt at an Apple OS - looks and feels great, but frustrating when something doesnt work and it WONT let you tinker without a fight.
8.1 - Without a touch screen it is painful to use, weird inconsistencies to how it switches between PC and tablet screens, nothing old works, even more restrictive than 7 (more like an unrooted Droid phone).
Worst of all, M$ seem to have got sooo desperate to shift boxes, they are allowing it to be put on devices that are far too weedy for it to work properly; a friend recently bought a Tosh laptop, (no touch screen), and it was soooo slloooowwww I though he had already picked up some malware on it.
I do mean REALLY slow, I have an old Asus EEEPC901 running XP/Win7 that responds faster when running in battery saver mode, although I will admit the 901 SSD has been replaced with a faster "Patriot" SSD
I think touch screens are easier to understand and use - in the same way a Fisher Price Cassette Player is easier to use than a Linn/Naim set-up - my 17 month old daughter has already mastered the iPhone and Lenovo P780 smart phones.
PS, I suspect XP is hanging around because there is so much sturdy, reliable office gear around that the manufacturers refuse to issue Win7/Win8 drivers for; I am talking to YOU HP !!!!! I bought a new office printer mere MONTHS before Win7 came out, yet you have NEVER produced proper drivers for it, so if I use it on a Win7 box I lose double-sided printing, collating, calibration, wireless connectivity, ...........