Subject: What is the preferred basis problem of the many world's interpretation?

I recently tried asking Madsci about objections to the many worlds 
interpretation before but it announced that it had already done so previously 
so it left me hanging.  However, in no place at all does the site specifically 
discuss the preferred basis problem or the probability postulate.  However, one 
search-hit refers us to this website:  

http://plato.stanford.edu/entries/qm-manyworlds/#3.1  

This site discusses the preferred basis problem but it's as clear a mud.  Can 
you please explain it to me in easier to understand terms?  It says that the 
quantum state of the universe can be decomposed into a superposition of an 
infinity of orthogonal states so which state do we choose (hence 
the "problem")?  What does this mean?  No one defines "orthogonal" let alone 
what it means to decompose a superposition into different states or how to do 
so.  Perhaps you could give two examples to show how one may arbitrary 
decompose the superpositional quantum state of the universe?  I assume 
that "preferred basis" means the basis for decomposition, right (choosing which 
state?)?  Also, if you would please, what is the difference between the 
preferred basis and the probability postulate?  It sounds like they are the 
same since a superposition is distribution of possibilities, isn't it?  I 
really need your help in this regard.  Can you PLEASE help me understand this?  
Thanks.

Re: What is the preferred basis problem of the many world's interpretation?