I would argue that Windows 2000 was the last decent version of Windows. Fast, non-bloated, ran DirectX and games better than Windows 98 ever did, and as stable an operating system as I'd ever run.
I'm still looking for a desktop OS where user logs in as root/system and all the programs and services run as limited accounts.
XP changes this to a parallel + delayed service start up, but 7 and 8 really focused on boot times.
Source: I did that. Twice.