Ah, I remember the Good Old Days of Service Packs! *sigh*
It's funny, because in one sense, Microsoft was forced to adopt the Linux/open-source model of running updates, modulo gathering them into a monthly release batch because otherwise Win Admins around the world would march on Redmond with torches and pitchforks (again).
I still have my WinXP SP3 and Win7 SP1 install CDs, oh, life was so easy.... :-)
When I worked for Paul Allen’s Vulcan Corp they had a stealth pipe back to Microsoft. The team got all their software, including Service Packs, directly from MS servers instead of the regular distribution path. I recall being directed to install a SP onto all of the NT and Windows 2000 server systems with a malformed package.
I bricked a half dozen systems before they discovered the flaw. I received was a certain amount of ribbing but that was tempered by the knowledge that our Sys Admin was responsible for the download and they had no test & evaluate program at the time.
Needless to say I didn’t last there very long.