PC gaming is kind of a continuum to me. I can draw hard lines at DOS > Windows and Win9x > NT-based Windows a la XP where compatibility mostly or partially breaks but you can play a lot of games made since the Steam era on modern hardware without much fuss.
Consoles really define the "generations," and the only console generation I'm really nostalgic for is the SNES era. Mine was always a Nintendo household, and the SNES was my childhood. I had an N64, I've gone back to play it, I'm not sure even Ocarina of Time holds up anymore. The thing I still clutch to from the N64 era is the music. The SNES though, sometimes I want to go back and play those old games.