Use the conductor, and you can use whatever you want to!
If you are running from a PC, and you don't need to use that for anything else, that is the best. If you have anything running it can impact the show. Since the audio is coming from the PC, any warnings or "you have mail" sounds are being broadcast along with the show music. So besides your show program, I wouldn't have anything open.
I also recommend disconnecting from the internet in order to prevent any downloads or updates. I also make sure that I don't have any virus or scanning programs running during the show times. Anything that would take away from the show running is better.
Finally, if you are running it off a laptop, I would say make sure it is plugged in. My laptop will slow things down to conserve battery power if it comes unplugged, and the show will becomes unsycned when that happens.