Windows 95, 98, ME, Whistler, Longhorn, NT 4.0...
So I've been searching for old Windows ISOs for quite a while and I thought you fellows would probably like them.
They're quite good to play old games on, VMWare, etc.
https://winworldpc.com/library/operating-systems
They even have BETA versions of operating systems. Windows Whistler is the beta codename for Windows XP (NT 5.1) and Longhorn is the codename for Windows Vista.
HUGE list of Serials (most of these OS's were before Windows Genuine Advantage, so any should work)
https://forum.winworldpc.com/discussion/6677/redirect/p1