Try Franz Liszt's "Dante Symphony" and "Faust Symphony" -- both good classical pieces for a rock fan.
And if you like Mozart's "Requiem," try the "Requiems" by Verdi and Cardoso.
I'll also second (or third) the Wagner recommendations -- you'll probably recognize the Siegfried Idyll from the movie "Excalibur" (along with "O Fortuna" from the Orff you just bought), and the overture to "Tannhauser" is one of my favorite pieces of classical music -- you just have to get past singing "Oh Bwunhilda, you're so wovely" in an Elmer Fudd voice while you listen to it . . . . ;-0)
Pat
And if you like Mozart's "Requiem," try the "Requiems" by Verdi and Cardoso.
I'll also second (or third) the Wagner recommendations -- you'll probably recognize the Siegfried Idyll from the movie "Excalibur" (along with "O Fortuna" from the Orff you just bought), and the overture to "Tannhauser" is one of my favorite pieces of classical music -- you just have to get past singing "Oh Bwunhilda, you're so wovely" in an Elmer Fudd voice while you listen to it . . . . ;-0)
Pat