This is a loaded question and probably should be left up for the professionals to answer. I wouldn't really worry about it until you get serious about trading. If you are as new as you claim then you shouldn't even consider doing live trading for at least half a year I would have to say. Then you have to assume you would be profitable.
The most I know about the taxes in the United States is that there are like two different options and that you have to decide before you trade but what you decide on isn't really enforced so you can decide later on which option to use. Obviously whichever option works best to your advantage. Personally I am not worried about such matter so thus I have such a half ass answer. You won't have to worry about such things for a long time. You have more important thing to worry about, like being a profitable consistent trader.
This should answer your question. It sounds very complicated to me and like swordofrue said Taxes are the last thing on my mind until I start making a lot of real money someday, in which I will have no problem paying the IRS their share.