Local Diseases

[Megas Methuselah]

While the sedentary peoples in Central and South America would have probably held the Spanish at bay at first, I think that they, along with those in what is now Canada and the US would eventually have been worn down by the Europeans' superior firepower,

Superior firepower? The conquest of the Aztec Empire had little to do with guns, and was largely a success due to native allies and disease.

and in the North also by the destruction of their sources of food.

What do you mean?

It would have been more brutal and taken a lot longer, but we would have done it eventually.

If disease was non-existent amongst the Native Americans, then the situation may have mirrored Africa and India. Trading colonies and so forth that would have eventually developed into a total claim/conquest on the two continents. Then eventual independance, mass expulsion of whites, and many, many wars. The natives would likely never have developed into minorities, but it is exceedingly difficult to imagine a world where the whites wouldn't have a couple continents in which to run away from their mess in Europe.