Traders and investors get taxed at the same rates, investors get the added bonus of discount capital gains.
To be classed as a 'trader' you have to be running it like a business. Ie, your shares are stock, so you buy and sell regularly. I doubt theres a number of trades you need to exceed, the whole thing would be looked at. If you sell your stock regularly and its repetitive then you'd probably be classed as a trader.