I have never beaten a Metroid game.
I finally beat it on my GBA a few years back...looong overdue.
Madden is too complicated for me now. 
I actually went on the internet a few years ago to memorize Pac Man patterns.
I find that most games on modern consoles are too complicated for me now, or more accurately, have too high of a learning curve for me to want to bother. I get some free time and I want to play some games, not sit there and spend 3 hours figuring out how to make Solid Snake move.
Back in '90, a friend of mine showed me a game he had gotten off a BB for his Commodore 64 (actually, a friend of his got it for him, because none of uu could afford a modem). It was a German game called "Party Girls".
Commodore 64 Strip Poker.....
I also have to add to the list...15 years ago when I was working a call center that received very few calls I amused myself by working on a spreadsheet where I was trying to list my favorite game that started with the letter A, then B, then C, etc. My top 26 favorite games by alphabet. Yup, I'm a nerd.
I also have video game OCD. I have to see everything in the game. Games like the Diablo series, I can't grind, I need to reveal all of the fog on each and every map I enter, every time. RPGs, good lord, I love them but I have to try every side quest, open every door. It is insanity.
Lastly, this is my favorite game right now, running in Survivor mode:
http://turtles.nick.tv/gsp/international/tmnt/games/sewer-run/UK/BUILD/main.swf