The Crash Bandicoot Series (PS1/PS2)
Twisted Metal (PS1)
Super Mario Bros (Nintendo)
Backyard Baseball (Nintendo)

Elder Scrolls Oblivion, no competition. I will deadset remember that game until I die. I still get chills when I hear the soundtrack sometimes, and sometimes boot it up just for nostalgia's sake.

Ragnarok Online
Return to Castle Wolfenstein

Half-Life 2 for sure.
It was the first game I ever completed from start to end. It had the elements that no game had back in that day. It was thrilling and awesome.

The 2nd good game of mine is Return to Castle Wolfenstein. It was the 2nd game I had completed from start to end. It was challenging and interesting together. Even thinking about the game, makes me want to play it again.

Half life my first game ever

Final Fantasy X and XII

Pokemon Colosseum
Pokemon XD
Mario Party 5
Super Smash Brothers Melee
Touhou
Mario & Luigi: Superstar Saga
Kirby & the Amazing Mirror (Had a Japanese version for no reason)

Pokemon Yellow! my first original pokemon game, 10-12 years ago haha, still play it sometimes :$

legend of Zelda Ocarina of Time changed my view of games... I had a crazy crush on adult Link. Such a nerd!