Xanadu’s muse-inspires-a-roller-disco story still strikes no sparks, but the ELO-fueled songs are as awesome as ever. The remastered CD is this Magical Music Edition’s raison d’être. Also among the EXTRAS: a frank (if fawning) look at how Xanadu crashed and burned. Cracks director Robert Greenwald, ”It was not a film rooted in…Paddy Chayefsky realism.” B