None of these are perfect and nostalgia plays a huge role ...
Legend of Zelda - This sucked me in and didn't let me go until I conquered it. My mom would help me and I would map out the dungeons on graph paper, I still have those maps somewhere ...
Final Fantasy - Although Zelda was big (for back then) I was stunned by the scope of this game. I still remember taking it out of the box, seeing how thick the manual was, then unfolding the world map and my jaw dropping. I bought it on virtual console a few years back (just so I didn't have to dig out the NES) and played it through and still found it fun. I played all the final fantasy games released in the US up until around FFX and although they got much better the original one has always had a special place in my gamer heart.
Perfect Dark - We wore out several controllers on Goldeneye and that would have gotten my vote but I remember being blown away when I figured out you could set your AI teammates in Perfect Dark to target other players specifically, or to guard you or a spot or what have you. Loved it.
Metroid Prime - a bunch of Metroid goodness and one of the tougher final boss battles I have ever played (when you combine the pre-boss battle with the final boss)
Mario 64 - Never been a huge Mario fan but this game was fantastic back in the day.
Tekken Tag 2 (Wii U version)- When I first got the PS1 we played a ton of games but we always gravitated back to the Tekkens when it was time to talk some shit to each other. To this day a group of my oldest friends still demand to try to dethrone me on a Tekken game (occasionally I let them so they want to keep playing).
Resident Evil - One of the only games I've ever played where we would turn off the lights and one of us would start playing while 7 or 8 people would be content to just watch, and occasionally jump when one of those damn dogs came crashing through a window.
ZombiU - The only game I have played since Resident Evil that actually caused me to get a tense feeling. Granted this one has it's flaws but it was quite difficult to beat in survivor mode. Also love the idea when playing regular mode of having to chase down your former body (now a zombie) so that you could get all your shit back.
Edit:
Conkers Bad Fur Day - I didn't play any PC games back in that era and this was my first introduction to a parody game. I also couldn't hardly believe the mature content on a Nintendo system. Can't believe I left this one off my original list.
