Do you wish gollum had lived?

[Sauron999]

Smeagol may have murdered his best friend to get to the ring, but does this compare the deed of Isildur in not taking the ring, and thus wrecking the best chance EVER of destroying Sauron, thus bringing peace to Middle-Earth. And remember, this was done after he had just taken the ring off Sauron.

I'd say that Isildur was overwhelmed by the ring just because he had taken the ring off Sauron recently. Sauron was more or less at the height of his power when he fell, and so was the ring. That could explain why Isildur didn't "want" to throw it into the Cracks of Doom: The ring wouldn't let him.
And at that time the wise knew that Sauron had created the ring to rule over all the other rings, but they didn't know about it's effect on men/elves.... or did they? Please correct me if I'm wrong.
But as far as I know no one had ever worn the ring but Sauron, so they couldn't know about it's effects. Maybe they didn't even know that Sauron would be destroyed with the ring, though Isildur must have known that the destroying would at least lessen Saurons power. But, as i said, the ring had much more power (in my opinion) than later on when Bilbo or Frodo got it.