Can you hear the sound of the DVD on the factory installed DVD player without the wireless headphones? If so How?

Yes. Press the mode button on the steering wheel until it is in DVD mode. This is how I do it on mine with Tech pkg. ;)

Ok, here's another stupid question: Can you turn the speakers in the front OFF and just have the DVD movie sound playing in the rear? Sure, you could fool with the fade/balance, but is there a simpler way???

Ok, here's another stupid question: Can you turn the speakers in the front OFF and just have the DVD movie sound playing in the rear? Sure, you could fool with the fade/balance, but is there a simpler way???
No. The way its set up, you can play the radio in front and listen to the DVD in rear on headphones or DVD on the whole thing. You can turn the rear speakers on and off, but not the front. ;)