hi. I’m a bit new to modern model railroading and was wondering.
My new railking “O” scale set came with the standard 3 rail track, but i have seen 2 rail track for the O gauge set-ups.
My question is can i switch to the 2 rail and still use the remote run unit that came with my set? and are there any real diffences with these two types other than aperance ?
No.
Yes, the 3 rail is an AC based system, the 2 rail is a DC based system.
Thanks nfmisso that answers my questions 
Also, in a three rail system the two outer rails carry the same polarity so there is no need to insulate the wheels and they usually aren’t for three rail equipment. Thus if you put them on two rail track they short out the power pack. Two rail track uses closer to scale rail and flangeways in the turnouts that three rail equipment can’t negotiate. In general you chose between the two systems for your trains and tracks. You can buy three rail track where the center rail is black to minimize its presence. Of course you also could have separate loops of each kind on one layout.
Enjoy
Paul