Windows Vista is a special case, it took a lot of flack that Windows 7 would have taken if Vista had not came before it.
Windows Vista broke compatibility(for the better of security) by making it so applications could only write to the User lever directories and would need elevated permissions to make system wide changes, Windows Vista also brought the first major x64 push from Microsoft, which left people with many peripherals that wouldn't work because there weren't 64 bit drivers available. In the time from Vista to 7 applications where updated to follow proper programming guidelines and 64 bit drivers where released, Vista in essence took the blow so Windows 7 could be a success.
In my opinion Windows Vista also has some serious performance issues, for example its caching was way too aggressive and would eat up all available RAM and leave little to none for running programs(I got out of memory errors in Photoshop while Vista had 700+MB of RAM "cached").
True, I never quite understood why people seem to hate Vista but love 7.
I have a laptop with Vista (and a recent SP) and 7 on my desktop. Besides a few UI differences I find it hard to tell them apart at all.
Most of the changes between XP and Vista that I disliked on Vista seem to have persisted unchanged in 7. I find network configuration much more confusing on Vista and 7 than on XP for example.
Perhaps earlier versions of Vista did have issues with memory management but as far as I can tell they have been improved by recent service packs.
I think it's due to poor management of the product and its release.
From my experience, Vista was hated due to very poor driver support, the ever-annoying UAC, and the fact that the new Aero UI (along with misc. other system services) took a significant toll on system resources.
At least the first 2 issues were both largely resolved via service packs, which is why you're probably not suffering much from those problems. The last issue was jointly resolved through some refinement of Aero, and the fact that the marginal resource cost became less significant once more powerful systems became available at cheaper costs.
The crux of the problem though, is that many people found under Vista that many of their devices quit working, their PC was slower, and they were getting pop-ups from UAC for basically everything that they clicked on.
Vista wasn't terrible per se, but it's negatives outweighed the positives for many people, and when you boil that result down to a binary value representing whether you think it was "good" or "bad", then the result is going to be "bad".
Windows Vista broke compatibility(for the better of security) by making it so applications could only write to the User lever directories and would need elevated permissions to make system wide changes, Windows Vista also brought the first major x64 push from Microsoft, which left people with many peripherals that wouldn't work because there weren't 64 bit drivers available. In the time from Vista to 7 applications where updated to follow proper programming guidelines and 64 bit drivers where released, Vista in essence took the blow so Windows 7 could be a success.
In my opinion Windows Vista also has some serious performance issues, for example its caching was way too aggressive and would eat up all available RAM and leave little to none for running programs(I got out of memory errors in Photoshop while Vista had 700+MB of RAM "cached").