How do you do multiplayer, it keeps telling me i need to be signed in?
You must be logged into a gamecenter account to use online multiplayer.
How do you make a discussion without everyone having to edit it to talk?
That currently isn't possible on wikis. That's just the way it works. But don't expect huge amounts of people on one discussion page at a time, there is a very limited amount of active users nowadays.
They should really add all the Items to creative mode,shouldn't they?
How do you delete a page?