In my opinion, although E.T. on the Atari was voted the worst game ever, my least favorite NES game back when 8-bit was king was Clu Clu Land. Something about it just made me want to do anything except play games. Hands down, my favorite game of all time is the original Zelda. I've played it to death on every Nintendo it's been available on, as well as emulators, but there is still something about the originality, puzzles, overworld, dungeons, and the variety of weapons and tools that make it my favorite.
I think the best game to play. You can wander to many location in a large map to find many enemy and gems. But also the worst game, as it's theme is moody & depressing (in a post nuclear war). And time consuming to finish all mission
Best games ever: Battlefield 1942, GTA III/VC/SA, Super Mario 64, NFS Porsche, C&C1, WarCraft III + Addon, Return to Castle Wolfenstein, No one lives forever (1+2)
Worst games ever: Gran Tourismo (the whole series), Call of Duty (Modern Warefare 1, 2, 3 + Black Ops), Battlefield 3 (because of Origin and console-"features")