I have a dead pixel should I wait for the next version for the warranty?
You're not getting a model for which you didn't pay. Either live with it or take it in and you'll get a 4th gen back.
When the 5th iPad is released, you may be able to trade yours in and pay upward to the new price, but they'll probably be suspicious of you waiting that long.
I bought a used iPad off of Amazon, it came with minor dents, but since it's been in my possession I had a little accident and dropped my backpack with it inside (it was even in a cushioned case) and now along the bottom of the screen is a crack, and in the corner it's shattered more. I have NO idea how their warranties work or anything of this type of situation, would I be able to do anything about this as far as getting a replacement? I'm not looking for an upgrade.
It was the iPad 2 32GB, Wifi + Verizon 3G, white, 2nd Generation
You'll be able to pay full price for a new one.