The entire experience of Silent Hill 1 and 2 are etched in my brain forever, especially the very effective storytelling that Silent Hill 2 had.

Portal is another game that I will remember forever, one particular part towards the end really caught me off guard and also had me laughing out or irony.

Castlevania 2 for it's very mysterious townspeople and their very cryptic conversations, the guy on the boat was especially creepy.

The part in Zelda Twilight Princess where everything was black and white was stunning when I first saw it.

The original Metroid was the first game I remember striking my imagination as a child and made me want to explore the world, even tho I found it frightening at times.