So, Mario is basically the most iconic video game character of all time, with more games under his belt than any other character ever. But which of these many, many games is your favorite?
And I'm not just talking platformers, either. Paper Mario, Mario Party, Mario Kart, etc, it's all fair game. If Mario is a main, playable character in a game, it's pretty much a Mario game (Hence why stuff like Luigi's Mansion and Wario Land aren't Mario games). I'll leave it to your own discretion whether or not you count Super Smash Bros as a Mario game.
As for me, at times I have trouble choosing between Mario 3, Mario World, and Mario 64, but overall, I think I have to go with Mario Galaxy as my favorite.
I mean, it looks great, it plays great, it's challenging without being unfair, it has a great final boss, the gravity-based gameplay is unique and inventive, it really has everything I could want in a great game.