I do not know which DVD to buy for coins.
Which is better; In The Beginning There Were Coins or Fists of Fury?
That all depends on how experienced you are with coin magic; neither one is "better" than the other, because they are marketed toward different skill levels. If you want to learn the basics (or reinforce them) and pick up a few tricks along the way, then get Noblezada's In The Beginning...
Otherwise, if you've been performing for quite awhile and are looking to learn a few new routines, then pick up Kam's Fists of Fury