Changing Ownership of iPad

I recently inherited an iPad from my dad and am wanting to change the ownership so that I can download books, apps, etc. to the iPad. When I access iTunes store from the iPad, it asks for his password, which of course I don't know and can't get.

I somehow managed to get the music from my iTunes account onto the iPad, and in my iTunes account it recognizes the iPad as an authorized device. But still, I cannot use the iTunes store on the iPad itself or add any apps to the iPad. Is there something else that needs to be done???

I've followed some of the discussions, but I can't seem to make the iPad restore. But then again, don't really know how to do it step-by-step. ie; does the iPad need to be plugged into my computer in order to do it? Or do I do it from the iPad as a standalone item? Where do I navigate? Sorry to sound so dumb, but this is really frustrating!

Thanks for any help!