My Sylvania Blu-ray player stretches all SD content on Blu-ray to 16x9, just wondering if all players do this? Kind of annoying I have to set the TV to squeeze the picture for 4x3 extras.

No, there should be a setting in your Blu-ray player's setup menu so that 4:3 material is displayed correctly.

Nice, I spent some time fooling around with the settings today and finally found it. The option is oddly named 16x9 Squeeze.