I love Top 10 Lists. Like for real:
I make a lot of them
I could probably think of a more detailed list if I had some time, but I feel something like this is better if I go from the gut.
NES:
#10 Ice Hockey
#9 Tetris
#8 Legend of Zelda
#7 Super Mario Bros
#6 Qix
#5 Zelda II: The Adventure of Link
#4 The Punisher (shut up, it's pretty damned good)
#3 Air Fortress (how does this beat out both Zelda games? Play it. )
#2 Pirates! (IF YOU HAVE NOT PLAYED THIS GAME, RECTIFY IT)
#1 Super Mario Bros 3 (of course)
[I know a lot of classic titles are missing, but my NES library was limited]
SNES
#10 Lawnmower Man
#9 Terranigma
#8 Illusion of Gaia
#7 Donkey Kong Country
#6 Final Fantasy IV
#5 Final Fantasy V
#4 Super Mario World
#3 Chrono Trigger
#2 Legend of Zelda: Link To The Past
#1 Final Fantasy VI
I don't really have a top 10 of gameboy games, but:
Pokemon Red/Blue, Link's Awakening, Heroes of Might and Magic, The Oracles games, Tetris and Super Mario Land 2: 6 Golden Coins
I might do the other consoles later.