I'm very much a fan of "classical," though as we use it today the term encompasses not only the Classical period, but also the Baroque, Romantic, and more modern eras in orchestral composition. The list of composers whose works I have enjoyed could go on for quite awhile: Bach (J.S. [the most famous one] and others), Beethoven, Brahms, Mozart (both), Strauss (all of them), Verdi, Wagner, Handel, Haydn(s), Tchaikovsky, Rachmaninoff, Mussorgsky, Khachaturian, Bizet, Chopin, Gershwin, and many, many others.
A couple of quick notes about previous posts: yes, supposedly Tchaikovsky was a homo, though many still debate whether that is fact or myth. As for "heavy metal," a music professor I had said that Beethoven essentially invented heavy metal, if you like, though I concur that such a sonic tradition was definitely continued through composers such as Wagner. The Gayaneh (or Gayane) suite...such an excellent piece of music; the Lullaby is stunning.