its incredibly difficult to compare to vastly different franchises. Pokemon is about collecting the pokemon, battling etc. and more recently contests, the game can go on till the ends of time, and with the competetive battling scene it one of those games that doesn't actually end. Pokemon has proven itself in the spinoff department also, but only by a few titles that weren't anything amazing.
Mario on the other hand deals naturally with platformers, his 3D iterations have him toppling harsh stages and gathering powerful items (usually stars) to defeat Bowser or whoever is standing in his way. Complimenting these platformers though are many many spinoffs that also prove to be very fun and of surprisingly high quality, Mario Kart is a lovely example of this, it has been around for an age sporting a wide variety of Mario faves racing on wacky tracks inspired by Mario themed places. There are also the platformer/adventure/rpg spinoffs such as the Paper Mario series, the Mario & Luigi games, and other random throwouts such as Luigi's Mansion or Yoshi's Island. These games have also proven themselves to be of brilliant quality and high re-playability. So much so that even the smaller titles such as the aforementioned Luigi's Mansion has Nintendo fans on their knees begging for a sequal. The Mario franchise is arguably the best fighter against the critically acclaimed Legend of Zelda series whose titles have proven to be the highest of quality, and even has one game known only as Ocarina of Time, that has people not only pondering the possibility, but outright stating that it is the "best game ever".
Recently though, Mario has been fending off even the legendary Zelda games with such mammoth titles as Super Mario Galaxy, currently ranked at an average of 97% on Metacritic. Now, i may be no expert, but if a game is ranked at such an extreemly high percentage... it's probably better than anything else you've ever played. The series is not without enemies though, ignorant teenagers who think they're too old to play Mario games, jealous Sonic the Hedgehog fans and general douchebags always try and bring him down, complaining that the series is too old and has gotten stale even though recent titles clearly say otherwise. Of course they cannot collaborate proper reasons for their hatred and are just embarrassing themselves by slinging out unneeded hate. Mario is not the only known face in the series, recent titles have Mario's main cast becoming more and more active, Super Princess Peach, a DS title starring the usual damsel in distress was released some time ago, proving quite successful, though not to the quality of mega hitters like Super Mario 64 and New Super Mario Bros. Mario has been a solid, influential name in the history of gaming and.... erm...wait, what was the point i was trying to make again?
Oh, Mario 6, Pokemon 1