I don't think I started PC gaming until after the Win2000 era, so I don't think I can be much help there. But if you need some ideas LGR is a good channel for old PC games:
Uh....for what it's worth, I don't know if these are Win2000 compatible and I could check but....fuck it...let me just list the old PC games I use to play: Rollercoaster Tycoon all the classic Blizzard games: Starcraft, Warcraft, Diablo Railroad Tycoon SimCity 2000 huuuuuuuuuuuh......that's all that comes to mind.
I forgot to mention System Shock - I know that's a DOS game. It also plays like one...god it's controls are clunky as hell. Can't wait for the remake to get released...could never properly finish it because I could never get used to it's clunky controls.
Kings Quest, Prince of Persia, Inherit the Earth, The Dig, Might & Magic series, Ultima series Labrynth of Time, Myst (if you like point and click adventure) Doom, Wolfenstein 3D, Duke Nukem
I think all of these run on Win2000 or there are versions that do.
I love Mechwarrior! One of my favorite all time games (built on the MW2 engine) is Interstate '76. The story is great and the funky 1970's soundtrack is the best ever. I used to play in online car battles over AOL dial-up.