Good "Heavy" Classical/Orchestral Music

^ Thanks for the amazon link, but I'm REALLY short on cash at the moment, and tbh I'd like to *purchase* it, and make sure I like it, before I buy. I can't afford to waste money on cds that aren't amazing at the moment, so is it really as good as you said it was? And can anyone else vouch for it?
 
Berlioz - especially "Songe D'une Nuit de Sabbat" from Symphonie Fantastique. It's dark as hell. I thought Wagner was dark until I heard this one.
 
All kinds of Danny Elfman, really. The Batman soundtrack has some of the best music I've ever heard on it.

Also with Stravinsky - The Firebird Suite, some dynamic sh*t.
 
Danny Elfman is an absolute genius, IMHO. I love almost everything he has ever done. If we're talking about soundtracks, the soundtrack for Bram Stoker's Dracula is very good as well (No, not Elfman. But still very atmospheric and very good).

Absolute "must have's" for any metalhead are Mozart's Requiem and Carl Orff's Carmina Burana. Others that I like are Holst's The Planets (Especially Mars, Bringer of War) and Braham's Requiem. Vivaldi's The Four Seasons was mentioned in the original post and I would consider that one to be another "must have."

Oh! Another of my favorite CD's isn't orchestral, but it's Elliot Fisk's transcriptions of Paganini's 24 caprices for classical guitar. Amazing guitar work.
 
Check out Hector Berlioz's "Fantastic Symphony", ESPECIALLY the middle section of V. Read the Wikipedia about the meaning of the arrangement. Dark and epic as hell. Not as playful as Vivaldi & co. though. If Vivaldi is the In Flames of Classical, Berlioz is the Opeth.

FANTASTIC CALL!!! I don't know how I could possibly leave out Symphonie Fantastique!!