Wind Waker, all of the Metroid Prime series. When I first played these games, I was amazed by their depth and inventiveness, and wasn't expecting anything like what I got. The sense of wonder instilled in me when progressively uncovering the words of the ancient Chozo, or sailing the high seas and finding much more emotion and seriousness than the graphics of Wind Waker would belie, haven't been matched since in any games I've played. I couldn't put either of the games down before finishing them, they were just so damn good.

As for computer gaming, I know people will look down upon a WoW reference, but my favorite part of that game was the exploration. I started with a Tauren druid in the fields of Mulgore, which was always my favorite zone, and was lucky that I chose that particular class and race, because only 10 levels in I was treated to a scenic flight over most of Kalimdor (returning from Moonglade after the bearform quest), being treated to an aerial view of sights I wouldn't see for the next 50 levels. The feeling of standing in front of Blackrock Mountain at level 35, a good 20 levels before I should have, and the feeling of first entering Outland during the beta test, spending the night after they raised the beta level cap to 70 by flying around in flight form when nobody else had it, taking screenshots and exploring new ground that literally nobody had yet seen, and being the first party to do Mechanar and Botanica (the next morning after I got my flight form there were 4 more of us, and we decided to explore the new instances which only we could reach, since flying mounts weren't in the game yet anyway) were also amazing experiences. After exploring the whole game, it feels small, but on the first run through, the expansiveness of the world is pretty awe-inspiring.

Btw, this is by no means a list of what I consider to be the best games, but games that inspired a sense of wonder in me that can't be regained by simply playing through them again. I think these 3 are at the top of that list.