I booked my package thru disney Travel and paid with my Visa card. Anyhow, I received my package about 2 weeks ago with everythin in it. I imagine you will pick it up when you check-in, but I am not sure about that....
Anyhow, the preferred seatings are little tickets they give you. You present them before hand and you either have a special section you can sit in, or they let you in for seats before everyone else. At least that is what I understand from reading everyone's posts on here.

So, no, you do not need to make ressies in advance. Hope that helps!