I recently finished a project which was for a client based in the US, trouble was I am Sydney based and really had to consider firstly how to shoot the gig and secondly how to encode it. I had no way of testing whether PAL would work on an NTSC player. SO I sent two test DVD's to the client based in Tennessee PAL &v NTSC. They played both without a hitch.
I just had to ensure my DVD regions were playable everywhere. I'm not totally up with the technical jargon for it however todays DVD players are smart enough to extract the content off the Disk and output the signal to suit.
FYI: I filmed it in HD using Sony HVR - Z1 and output it via DVD Studio Pro.