Started with a ZX Spectrum (Horace goes skiing!) then got a megadrive played several of their games nothing totally amazing though. Then on to playstation eventually, Doom and Tomb Raider!! When I discovered PC gaming it was first guild wars then COH then WoW.. Aion... Rift... Lotro.. SWTOR.. and now I am waiting patiently for Wildstar.

This... and Super Mario Bros when I was about 5

My first one was Super Mario Bros on NES. The NES and SNES are hands down best consoles ever to me.

^^ This. Super Mario and Super Mario 3 were great (I still play Super Mario 3 on my NES), then there was Donkey Kong on SNES...but the game that really did it for me was Super Mario RPG: Legend of the Seven Stars. I rented it from Blockbuster and it was all downhill from there. I went to try and buy it recently (I still have my SNES, too), but it's so expensive now!! The last I saw it was going for $80.

The first games that turned me into a gamer were probably Super Mario World, Super Mario All Stars, and Kirby Super Star. Then as a teen I got hooked on RPGs through Final Fantasy X.

Pac-Man had me hooked, Legend of Zelda reeled me in.

I go back to the Atari 2600 so Pitfall, Ghostbusters and Smurfs got me into gaming. When the NES hit the scene, Mike Tyson's Punch-Out, Super Mario Bros and Legend of Zelda solidified my lifelong gaming addiction. When I discovered RPG's like Dragon Warrior and Final Fantasy i knew I was going to be dumping constant hours of my life into video games and I've loved every minute.

While I obsessed over many games with my original Nintendo, Zelda, RadRacer, Duck Hunt, ExciteBike, etc., and Castlevania at my dad's (he had a SEGA), it wasn't until we sat down to play Dr. Mario that we call got well and truly hooked. I have 3 younger siblings - my sister, then my brothers, so we would stop and play tournament style against each other, etc. However, my most worthy opponent, the one who talked the most smack to try to psych me out was my MOTHER! I still remember, we were trading insults one day, and she called me "Cat Fart!" and threatened to send me to Siberia (I have family from Russia). It is still a running joke between us today, though neither of us play that game/system anymore, that's when we knew we were hooked.

Final Fantasy 1 for NES, sat there watching my dad play, he said I couldn't unless I knew how to read...so I learned to read, then I played the game...and here we are =D

Shining Forces for Sega. When I played that "for just a minute" and it was 5am the next morning before I knew it, I was hooked on RPG's for good.

I think it was Sonic the Hedgehog....I still remember him tapping his foot waiting for me to go
After that I was on an endless quest to get my own console.^^

Probably Skyrim. And Warriors Orochi

I'm going to really show my age I reckon!

First game to get me on a "console" was a Hanimex system with a light gun to shoot a square box moving on the TV screen. To date I've never owned another console.

First games on a computer were on the C64. Many great titles I played over the years but I think the defining one was "Gateway to Apshai", but it's a tough call. I wonder how many others here played it?
http://en.wikipedia.org/wiki/Gateway_to_Apshai

For PC the first one to really seize my attention might have been Syndicate, but again, so many awesome games over the years. However, most fond PC memories in the early days belong to Scorched Earth, which was simply brilliant.
http://en.wikipedia.org/wiki/Scorched_Earth_(video_game)

Later life in PC gaming we hit RPG, FPS and MMO games. Bioware wins on the RPG stakes, I call Planescape: Torment as the best of them. Delta Force/DF2 were my picks for FPS, MMOs I played a lot and whilst I don't think WoW is the BEST of them its certainly the one I played the most.

Tabletop gaming was started by Battletech, currently playing Warmachine/Hordes more than anything else (which isn't much these days, I prefer to paint than play), but I have armies for many non-GW games.

HOWEVER, all that said, the games that have defined me as a gamer, since I was 8 years old to this day are pen & paper RPGs, and the king of those for me has been D&D. I've made international trips due to that game, and spent 20+ years working on my own game world. I DM two different groups currently and am always writing new stuff for my games.

Pitfall!

Ultima III and Elite on my Commodore 64 probably hooked me. I don't think I ever really finished Elite though I came close. I'm tempted to try one of the ports just to see if I can complete it.

Definitely Starcraft. Then Ultima Online. I had a Nintendo and a Sega before that, but never was (and still am not) at console games. PC games or nothing for me.