My new projector has arrived with a number of leads included. There are two that puzzle me. 1 has three RCA on one end (RGB) and a DVI connector on the other. 2 has three RCA on one end (RGB) and a 9 pin "D" type connector on the other. The projector has inputs for both of these and also S-video and composite. My dilema is which to use for best picture quality?? Help please.