So they keep telling me I can have a free update...would you?
Personally I have used Windows 8 on my mums computer and I hated it (better after the upgrade when you could get the classic view). Avoided Vista.
I also didn't like Windows 7 - but have got used to it now....I tolerate it - came from XP which I still prefer for some things - (will admit XP was an improvement on 98, 95 and 3.1)
I hated 'my documents' etc and stopped using them after getting onto a work server replaced and over wrote my account...(I had backups -it still took hours to sort)
But I detest libraries and the fact that you can't (easily in 7 anyway) get rid of them. I have to the best of my ability/patience but still Windows sometimes tries to send things there - no let me tell you where I want this to be!!! 
I have a personal folder system 'asafedocs' that I love and works - it is on the D partition -safe from overwriting! I do voluntary work for 4 different groups, plus have my personal stuff and children's stuff etc. I want to have all the files etc associated with each group in its own folder - if nothing else so I could just copy it all to a memory stick and pass it it on to someone - not a poster in jpg mixed in with my personal photos! And searching isn't quicker if you have lots of files with similar names covering many years (eg 'group X' Accounts 15-16, Group X accounts 14-15 - a search never pulls up the oldest unless I type the whole thing in -and sometimes you want the list in front of you to go through - or aren't sure exactly what you would have called something but know where you would have put it...sorry rant...I really hate libraries!
I also hate it when Windows tries to guess what you want to do.
Also I ditch MS Office a few years ago -now use Libre/Open Office.
So would you upgrade to 10? ...or am I going to find it infuriating...