kleineme: i should change my wording to make it clear: if you won against a master who play without two knights, then you can call yourself a first dan, the lowerst ranked player. you begin to know the game, otherwise you are just a layman.
as to two knights handcap game it is played between two players one is stronger than the other. the center pawn is capture if the piece did it by deliver a check, this is the rule, the center pawn is called "the iron pawn", if it had been moved, then it is no more an "iron pawn" i don't know how you could play the two knights handicap online, unless you write a special program to do it. there are one knight handicap, 3 moves, two moves and 1 move handicap etc.