Minato is far from Madara's level,only fanboys would say teh contrary.
Quite the contrary. Minato is certainly on the level of Madara (living Madara). Jiraiya stated he was the most talented shinobi he ever met, and he taught Nagato with Rinnegan and Naruto with Kurama. Whether Minato can beat Madara is a whole different matter, but you have to admit Minato IS on Madara's level. After all, you dont get given the title Hokage with the only things in your arsenal being a few sealing jutsu, speed, and a powerful ball.
Minato can make a strong case as to why he can beat Madara, although according to reputations, Madara's easily eclipses Minato. His very name caused a fricking war!! Minato's rep isnt too bad either: "During the Third Shinobi World War, flee-on-sight orders were given to enemy shinobi should they ever see him appear on the battlefield." Now whole platoons dont flee the battlefield after seeing you for no reason.
Firstly, in terms of powerful jutsus and raw power, Madara beats ANYTHING Minato can throw at him (Katon...>Rasengan). Madara also has great genjutsu, Susanoo and Amaterasu, although genjutsu and Amaterasu wont work on Minato as hes too damn fast. Against Minato's speed, Madara's best jutsu is Susanoo. FACT.
Madara's greatest weakness happens to be Minato's greatest strength- intelligence and perceptiveness in battle. From what we've seen, Madara can only overpower opponents instead of outwitting them, outmanouevering them. Minato's intelligence is his greatest weapon. He figured out Tobi's immaterialisation jutsu and owned the masked man. Throughout the series, intelligence > power. Based on power, Shikamaru should NEVER be able to defeat Hidan, yet he did! Itachi figured out a weakness in one of the strongest jutsu's ever, Chibaku Tensei; a jutsu used by the Sage of Six Paths himself, albeit on a larger scale. After just hearing Tobi speak, Minato gauged his strength and thought about all events past and concluded that Tobi's Madara (right or wrong we dont know yet, maybe a twist coming?). Tsunade remarked, "That man never wasted a movement." Everything Minato does is calculated.
Itachi said, after seeing Chibaku Tensei, "Every jutsu has a weakness." In this fight, Madara will be forced to activate Susanoo, and there is a strong possibility that after seeing it in action for some time, Minato can figure out a way to beat it. Minato has been shown to be one of the most perceptive and intelligent shinobi ever. IF there is someone who can find a way to beat Susanoo, its Minato.
Either Madara will outlast Minato, or Minato will outwit Madara. Minato's space-time gives him a HUGE edge over almost ALL of Madara's jutsus. He also has a bloody impressive defence himself- space-time barrier. I dont see how Madara can beat Minato. All I see is a draw/win for Minato. Im NOT saying Madara's stupid, just not shown to be as intelligent as Minato. The man could foresee that only a person of incredible power could beat Tobi, hence giving Naruto half of the Kyuubi. Dont misunderstand me, Im not saying Madara is bad in any way, just that Minato has the perfect skill set to beat Madara. Minato is most likely Madara's worst matchup, mainly due to intelligence and speed.
Also, Minato created Rasengan. People seem to forget that Minato wouldnt have gone to the trouble of creating a S-rank jutsu if he hadnt already mastered powerful jutsus that he thought weren't powerful enough. Im sure hes mastered the hardest and most powerful jutsus of his nature, and that he wanted to create something even greater, hence spending three years on the unfinished Rasengan. Minato DEFINITELY has other powerful jutsus in his arsenal.
SIDE NOTE: Prediction- Minato will come back!!! Tobi needs ALL of Kurama's chakra in order to resurrect Ten Tails, and half of it is with Minato. Im guessing the scroll Suigetsu is a way to reverse the death reaper seal, bringing Minato and the yin chakra of Kurama. Tobi will then have to remove the chakra to create the Ten Tails. Minato will recover and fight alongside his son!!