Win2k was the NT line, which was generally more stable than the main Windows line, but couldn't play games well and didn't have any real consumer penetration. WinNT 3.1, 3.5, 3.51, 4, then Win2k (the first server version to not use standard version numbers), then WinXP, which was the version that merged the home and workstation/server lines, but also continued the home version tradition of sucking badly every other version. Vista, 8, and now 11 fall into that list.

I did use 2k back in the day and while it wasn't as good as XP, it was a serviceable work platform. Don't ask me about any issues on the server side, I did very little with that.