Okay, so I've got six Starter accounts (Wow1, Wow2 , etc). I bought the full game (all the way to Cata) and I'd like to install it. What's the best way ? Using the DVD's ? Download the full game client ? Can I keep using all my six accounts (and the characters that go with them) ? I tried entering the serial on the battle.net site but it asked me to choose an account to apply it to. Does this mean I can only upgrade one trial/starter account ?