Paper Mario and Paper Mario The Thousand Year Door are the most enjoyable Mario titles by a wide margin for me personally. As far as platformers go, the ones I enjoyed the most are Super Mario Sunshine, 64, and Yoshi's Island.
My favorite is Mario Sunshine. He can do so many cool jumps and climb really high with FLUDD. I also like Paper Mario The Thousand year Door even though it is the only Paper Mario I can't beat.
3D world is great. Have to say I was quite disappointed with Marino kart 7, not sure why, was just expecting more I guess. I quite like the new paper jam but I haven't played it too much yet
though tbh there's quite a few other mario games that are also brilliant imo:
- super mario sunshine
- paper mario: ttyd and super paper mario
- luigi's mansion 2/dark moon (if that counts)
- mario kart wii and 8 (if they count too)
- super mario maker (...again, if that counts lol)
- super smash bros. melee, brawl and wii u (though they probably don't count, but i thought i'd mention them anyway because mario characters are playable in all of them)
- - - Post Merge - - -
super mario galaxy 2 was the best imo.
though tbh there's quite a few other mario games that are also brilliant imo:
- super mario sunshine
- paper mario: ttyd and super paper mario
- luigi's mansion 2/dark moon (if that counts)
- mario kart wii and 8 (if they count too)
- super mario maker (...again, if that counts lol)
- super smash bros. melee, brawl and wii u (though they probably don't count, but i thought i'd mention them anyway because mario characters are playable in all of them)