If you believe in hell and are teaching your children your religion, then you need to explain what hell is. And it would be much better to teach your own children then to have someone else teach them their 'ideas' be it a firey pit or non existent.
I'll be teaching MY children what I believe hell is. And the idea that you'd threaten your children with eternal damnation for pushing their brother or not doing their homework is ridiculous. People who do that aren't right in the mind and are probably already abusers in other ways.
Children who are learning about God will question what happens to 'bad' people, exactly as I did as a child, adults are still questioning that here. You have to answer this when you're teaching your children about your religion and God and it'll always be age appropriate.
People who don't believe in God would ofcourse prefer children not be taught these things because you find them distasteful, lies, whatever. But when you grow up in a house where religion is taught and part of your culture it's not feared.
I had a crucifix above my bed since I was a baby and these things were in our house, I never feared a crucifix because we were taught it's protection and sacred. If I ever had a bad dream my mum would put the cross under my pillow and I'd feel instantly better. Religion in our house was never used to threaten us or used in a bad way, I always felt comforted by it. I think alot of the ideas put forward about hell or forgiveness of sins are catholic ideas, whereas we were never taught this and confession is not part of our religion.