For Sonic game's in my opinion I like most except for a few recent ones. My favorites are Sonic Heros and all the Sonic Adventure games, my least favorites are Unleashed,Colors and Black Knight seemed okay but it looked like SEGA giving a rip off version of the Legend of Zelda series. Personally they should put the new Sonic games on Gamecube and Dreamcast because they have WAY BETTER CONTROLS THAN WII.
Not really.. I have both a Wii and Wiiu and personally the normal Wii is crap, and Wiiu games are a rip off, only thing I like is the little cheap tablet board that comes with it. The only problem I had with GameCube was it would overheat sometimes if i'm like playing for 7hours or more when I first got a game.
Favorite 2-D: Sonic 3 and Knuckles (the combined one). Nothing's quite as satisfying as going Hyper Sonic and kicking everyone's ass. 3-D: SA2 battle - because Chao garden. Spinoff - Sonic Rush/Sonic Rush Adventure - these games were very well-polished and fun to play.
Least favorite 2-D: I don't really have one. 3-D: Unleashed - I never played '06 (I always really wanted to though! This video got me hyped for it: [link] And to this day I'm shocked that people say it's a bad game.) Spinoff: Chronicles: the Dark Brotherhood - this game was boring as hell. Boring.