I know a lot of people would argue with me on this, but the game I always get reminded of when thinking about what a perfect game means to me is Skyward Sword, and that is because personally, one of the things I like the most about games is their ability to get you immersed in its world, characters, etc in a way that movies and such simply cannot mimic.
The level of immersion and pure fun I had with that game was the biggest I've ever had while playing a videogame, and to me that is because of how everything blended so well in that the music, artstyle, gameplay and story were simply so good for me to find any issues with it.
Most of the flaws people have with this game, like the motion controls and how the overworld was ''small and linear'' weren't a problem at all to me, and that's something that I can't say about, say, Twilight Princess, which I thought had an unnecessarily big map and felt like it was a good game but it was still missing something to make it special.
Sorry for only using Zelda as an example, but that's the franchise that gets the closest to being perfect imo, even if it has its flaws (Like any other series). Also, I hope you guys can understand what I tried to say, I'm not a native speaker so my english skills aren't the best =P
