The Vikings settled briefly in Newfoundland, and there are remains there of their settlement but it only lasted a few years at most. The natives were apparently not friendly.
Well, it shows that America was just waiting to be discovered, and some sort of contact was inevitable.
It is difficult to think of a point at which the contact was peaceful or at all congenial. Surely the Spanish contact was genocidal, lead by a pack of misfits and freebooters, and laying the seeds of prolonged suffering and disaster lasting to modern times.
The New England contacts were initially much more peaceful, but even friendly contacts between greatly differing cultures are difficult to sustain. The King Philips War, in which the Indians wiped out several towns, led to an unrestrained war of survival, and poisoned relations between Europeans and the Indians for centuries.
It is difficult to think of most of the early explorers as truly great people, when they had so many moral faults, and were no more advanced in their cruel behavior than the savages they encountered.