Well, that depends on your beliefs. If it's a really minor thing I believe that God will take you aside and say "Listen, this is no reason to send you to hell. Just apologize and we're cool."
Given the Old Testament law code that was supposed to have been given by him, I doubt it. There are punishments for many things, far and wide, almost all of which are death.
If you're talking about not believing in Christ, well, my pastor equates it to going to the doctor's office, and the doctor says "Sir, you're very sick, but it's treatable if you take this medicine." But then you say "But I don't want this medicine, I'll find a better way to get cured." And then when you die from your illness, you seem so surprised even though you were given a very simple cure, but refused to accept it.
I equate it to mafia extortion, myself. "That's a nice immortal soul you have there. It would be a shame if it were, say, tortured forever and ever in a lake of fire. Perhaps you just go and devote your life and mind to me, so we can forget this conversation ever happened?"
As for hell itself, some of the churches I know vary whether hell is a fiery hole, or varied to suit your sin. Like if you were a thief all you're life I imagine hell as being placed in a museum of priceless artifacts from all throughout history, each one worth more money than you can spend in a lifetime. Only problem is, you're totally surrounded by laser wires and if you move even an inch you're caught and brutally beaten by dozens of armed guards. If you were Hitler, on the other hand, I think you'd be forced to live through the Holocaust once in the shoes of every man, woman, and child you sent to die. And then when that's done he can live through the lives of every German soldier he sent to die on the frontlines. If he runs out of people after that then he can spend eternity in a hall of mirrors with the ugliest, most Jewish (in his eyes) face one can have.
For the thief, a much better punishment would be to have hell be a land where he owns everything and there is no security of any kind. Why? There's nothing to steal, the action that brought him a rush of excitement. Even if the security system is truly and utterly impossible, he still has an eternity to try.