You can choose "skip this" at each of the initial prompts and have a completely functional iPad without registering for anything or entering any other information. Before iOS 5, you had to connect to iTunes on your PC or Mac but that is not required since then.
The first time you really will need an Apple ID is when you go download an App from the App Store (which will be soon enough :)). There also, if you choose an App which is free (like facebook) and you try to download, you will be prompted with a No Payment option to associate with your Apple ID which can can use to downlaod anything. The first time you buy something is when you will need payment information (credit card billing address etc.)
The first time you really will need an Apple ID is when you go download an App from the App Store (which will be soon enough :)). There also, if you choose an App which is free (like facebook) and you try to download, you will be prompted with a No Payment option to associate with your Apple ID which can can use to downlaod anything. The first time you buy something is when you will need payment information (credit card billing address etc.)