I could never live on a stranded island for the rest of my life with only 1 CD, no matter what CD I brought I know I would eventually tire of. So what I would do is bring Cannibal Corpse's Tomb of the Mutilated and blast hammer smashed faced while I bash my brains in with a rock, screw trying to hang myself like Tom Hanks on Cast Away.
Fuck that, I'd rather take all of these... Choosing only one is impossible.
Scythe - On My Way Home
Bal-Sagoth - The Power Cosmic
Pink Floyd - Wish You Were Here
Gentle Giant - Octopus
Negură Bunget - Either 'N Crugu Bradului or Om
Nazgûl - De Expugnatione Elfmuth
Mithras - Worlds Beyond The Veil
Louis Armstrong - All Time Greatest Hits (Does this count? Cause I would most likely take this along if compilation albums are allowed)
Gustav Holst - The Planets
Dissection - Storm of the Light's Bane