This is a tough question, because it puts two "one year wonder" type players up against three multi-year contributers. I think Banks was the best QB we had in the decade, but between him and Tate I would have to give the nod to Tate because he single-handedly carried the offense for a year and led us to a great season despite having less talented support than Banks and dealing with a multitude of injuries, and also having two other statistically solid years. Kaeding was great but its hard to give the nod to a kicker, even if he was the best we've ever had. Greene was amazing and arguably the most dominant player in the country for a season, but in the end I voted for Gallery. Not only was he a multi-year contributer, but unlike Tate he was dominant in every season he played in. He was the best player in the country at his position and I personally think that consistent excellence has to get the nod over one great season.
An interesting thought though... after the turnaround we had last season and what he meant to the team this year... couldn't another great season put Stanzi at the top of this debate? He was the QB during last year's amazing run and was the heart and soul of this year's offense and orchestrated a couple of the better comebacks in our recent history this year on our was to an Orange Bowl berth. If one great year and a BCS game was enough for Banks to make the list of finalists, wouldn't one more good year put Rick right in the same category? I know its all hypothetical, but I think its worth noting that even though he hasn't been the most consistent QB, he has a chance with one more good year to give us two BCS games and finish as the second winningest QB in Iowa history. I know next year isn't technically part of this decade, but he played the majority of his career in the 2000's and I think that if we have a good season next year, when people look back on this stretch ten years from now, its quite possible that the guy who could be remembered as the best player isn't even in the debate right now.