The first computer games I played were on a friend's Amiga - I was introduced to Gunship 2000 which took about half an hour to load off a tape drive. Around that same time my friends got a Nintendo and we played the hell out of Super Mario, and I got a Sega Master System. I guess I would have been 7 or 8.
Then after my Sega died and I didn't see my friends very often, it was playing Stealth Fighter F117-A on my uncle's PC. he also had Gunship 2000 and thanks to the upgrades in technology the game loaded from the hard drive in only a minute or so! Later he picked up a disc that came with Duke Nukem, as well as a fantastic SHMUP called Major Stryker.
My gaming was restricted to PC only from about age 13-18, but there were a lot of great games (mainly RTS and FPS titles). When I was in 12th grade my friends and I had a free double period on Thursday afternoons and went to a local net cafe to play Counter-strike.
At age 19 I bought a PS2, and I've been a console gamer since. A few PC titles got my attention (Sims 2, Galactic Civilizations) but I went from PS2 -> XBox -> 360 -> Wii and most recently PS3. My PC really couldn't handled gaming these days and honestly, I think I prefer to play on consoles. I play more this way than I ever did on PC.