Were the Spaniards and Columbus the greatest explorers of the new world?

Did you know that Spain abolished slavery in the New World and tried to protect natives there in 1542? The Spaniards brought Christianity too. I believe Columbus was a great explorer, but did not treat natives well. Still, we must all be grateful to Columbus for discovering the new land for Europe. The natives were somewhat primitive, and did deserve better treatment, but they were technological inferior to Euopeans, so they were conquered. Today, they are given special privileges in America and owe much to Europeans for giving them modern society.