I've never really had to share a family computer. My Dad was self-employed when I was young, and he went through quite a few computers and monitors as he had to upgrade at least every few years to keep up. He'd let me have his old computers (as opposed to taking them to the dump). Hooray for The Sims at 5 FPS and constant freezing (still loved that game, playing it legit or just burning houses down)! Can StarCraft lag (outside the N64)? Why yes it can: have you played it on a Pentium 2 @233MHz? 8 players will tank your framerate, bro.
Used to have LANs in the basement with a collection of old computers he didn't use anymore. Played lots of Counter Strike, StarCraft, Age of Empires 2, WarCraft 2 and then at the pinnacle of it all: WarCraft 3 (multi player spawn installs were awesome). Had 4 bricks and ancient, huge tube monitors, but we could still run WarCraft 3 at playable levels (This was about when Oblivion was new, and Dual Cores were showing up maybe?). Had like a few Pentium 3s at like: 533MHz, 600ishMHz and 833MHz. But then we had an AMD Athlon at just over 1GHz (that thing was a relative beast, everyone wanted that one when we played, haha). Lots of fun LAN memories. We were years and years behind in tech, but I was such an inexperienced PC gamer, I didn't know what I was "missing"--aside from Oblivion, which I never had a fast enough computer to run until much later, after I'd lost interest.
Short answer: no, I was privileged with computers (albeit slow, old ones), but still, very privileged.