Seeing this page made me notice the professional look of Windows 2000 Professional. I wonder why. I don't think it has to do with the word 'professional' but with the blue color and the white top. Also the gray is warmer than most Windows versions.
I remember those days at the library, where one could browse the internet, download stuff, but could not run any of the downloaded files. I then figured out that if you renamed an executable into SETUP.exe, it would run without questions. Then the library computers got cluttered with warez, music and games.
It also really reminds me of the 90s and my first computer, an IBM with a Pentium clocked @ 200Mhz with 64MB of RAM and running Windows 95. I got good use out of that thing.
I played a lot of MechWarrior 2 and SimCity 2000 on that thing. I was still a kid in the 90's. It kicked around in my house until 2000/2001 when it was finally replaced with a Dell Dimension.