Yeah, you'd have to have a Bluetooth in each ear to hear music in stereo, but most phones have MP 3 players in them so you'd get mono sound, the left or the right-hand channel. Don't know if that's currently available. I believe the Iphone and other newer phones which have MP3 have a stereo headphone jack.
Of course, don't check out BluRay discs if you don't have the player -- they are unplayable on a standard DVD device. BluRay is also capable of a 1080p picture which simply means it has the same number of pixels horizontally and vertically so it scans progressively across the frame instead of interlacing the pixels. It's a sharper picture with more detail with a BluRay disc if you have a 40" screen or larger, otherwise you're unlikely to notice the difference. There is some 1080p on satellite TV but it's pay-per-view. Blu-Ray is capable of full PCM sound in 7 and even 9 channels. Bottom line -- unless you have a 1080p display and super sound system, don't worry about it. Right now, if you have an HD TV, I'd buy a DVD upscaler player which improves the smoothness of 420p to the highest definition your display is capable of handling.
The multi-layer disc is capable of storing an entire TV series in standard defintion (older shows like The Avengers) on one disc.