I have a first gen iPad and am pondering upgrading to a new one. A few questions though:

1. To transfer my iTunes, I should just be able to tell it to allow that device, and then will have access to all of my iTunes, correct?
2. If I have 5 devices already with that iTunes account, I should just be able to tell it to deactivate that device, right?
3. As far as the apps I've previously purchased, do I lose them and need to purchase them again?
4. If I don't, and the iCloud stores them somehow, how do I then re-download all of them to the new iPad?
5. How do I ensure that all of my information is deleted before looking to sell/pass along the old iPad?

Thanks!