Is there a way to turn off respawning? I would like to play through once with a character that will remove all threat in Skyrim until it turns into a peaceful utopia and see what level I will end up at.

It should be possible via a mod on PC. But I know of no one who has made such a mod yet. There really isn't much call for a no-respawn mod.

If you're talking about one of the consoles, the answer is no.

You're right. I just thought it would be fun to try once if you could turn it off somehow.