Yes. Blu ray disc are more expensive than regular DVDs because it is an optical disc storage medium designed to supersede the DVD format. The standard physical medium is a 12 cm.
For a few reasons: Blu-Rays hold up to 5 times more data than a standard DVD. Blu-Rays have better sound and picture quality. And Blu-Rays have a special hardcoat layer on the bottom of the disc that...
Yes they most certainly do! (At least most commercial Blu-Ray players have no difficulty playing commercial DVD material)However, if you have burned your own files onto a DVD then you may not be able...