Toss up between Fallout 3 and Uncharted/Uncharted 2

I'll probably go with Fallout 3 because i got way more hours out of that game. 

Mario 64---My favorite game of all time...great graphics at the time..beautiful worlds..great gameplay..unforgettable music..just a masterpiece

Uncharted: Drake's Fortune. 

I'm guessing you haven't played Uncharted 2? lol

I'm going to be boring and say Ocarina of Time.

From beginning to end, that game is perfection.

LOL I love Uncharted 2 but to me Drake's Fortune is the best single player experience I've ever had. A lot of the plot and twists in Uncharted 2 were expected. I also liked the setting, the character development, the supernatural twist, and the villains much better in UC1. I really thought Sully had sold drake out, I had no idea those creatures would come and completely change the pace of the game, I didn't see it coming when Nevarro killed Roman, I liked having to team up with Eddie Raja to survive. Uncharted 2 just had cooler levels like the train and jumping from truck to truck and the stealthy(if you so chose) crashed train arena. But the atmosphere almost seemed way too fake for me to actually feel the same attachment as I did in the first one, especially in the second half of the game. My willingness to suspend disbelief was tested because of how much the first game was rooted in reality compared to how little the ending of the second game was. It also took me out of the moment when there would be the generic red dresser to climb on top of for the 20th time  in the middle of nowhere when it had absolutely no business being there. I could start to feel as if i was sitting in the chair with the guy designing the levels rather than being in the world that was created. Of course I didn't feel that way in the big action levels, they obviously spent way more time designing those.

Ever?  Definitely the original Legend of Zelda.  There was nothing like it before its release and when you've completed it you get an entire remixed second quest.  Heck, even the box and the shiny gold cartridge impressed me.

But talking strictly this gen, I'd say the original Bioshock.  Superb writing and voice acting combined with the outstanding story twists and revelations (finding out who you really are... and who Atlas really is) made this experience anything but just another FPS to me.  And Rapture itself, every room and hallway, just a pure delight to explore.  My only perfect "10" so far this gen.

Going to have to say Ocarina of Time. One of my first ever video games to own and the sheer quality of the game was just instantly imprinted in my mind.

Shining Force III saga (Scenario I, Scenario II, Scenario III and Premium Disc), for the Sega Saturn.

I still own all 4 discs. :)

Unfortunately this wonderful series was only fully released in Japan and most of the world couldn't play it.

Great insight.  Although I have to disagree about UC1 being better.  But it's your opinion and there's nothing wrong with that.