I think that, while entertaining, it would be expensive and not add much more capabilities to what's available now in mobile audio/video (also ignoring all of the installation headaches).
You could get everything you listed (aside from CD burning) from:
(1) Head unit with mp3 capabilities and an aux-input (mass music storage w/15 CD's worth of music on a single CD) - less than $200.
(2) LCD screen in visor - $130 - add more if you want throughout the car.
(3) PS2 - $200 - There's your DVD player and gaming center.
Grand total of a little over $500. BTW, there are also other options for mobile mass music storage like mp3-capable CD changers and mobile hard drive type devices (some act as a player while some are controlled like a CD changer).
