Well, all I listen to is classical. If you really want to know what specifically I usually listen to when agsing though...
Tchaikovsky- Swan Lake full ballet score (very appropriate for my game actually), Nutcracker full ballet, Symph. 6, Orchestra suites 3&4 (Mozartiana), 1812 overture, Capriccio Italian, March Slav, various small works
Vivaldi- Four seasons
Stravinsky- Rite of Spring, Pulcinella (occasionally, it's not that good)
Saint Saens- Carnival of the Animals, Danse Macabre, Bacchanale (Samson & Delilah)
Mozart- all kinds of crap, mostly piano concertos, eine kleine nachtmusik, opera stuff (Magic Flute, Marriage of Figaro)
Holst- Planets (Jupiter's my favorite
Handel- Music for the Royal Fireworks
Mussorgsky- Night on Bare Mountain, Pictures at an Exibition
Puccini- various opera stuff (Gianni Schicci, Turandot)
Mendelssohn- Symphony stuff, Midsummer Night Dream, Songs without Words
Beethoven- Symphonies (usually pastoral(6) and Eroica(3)), piano sonatas, etc...
Wagner- Flying Dutchman, Tannhauser, Mastersingers of Nuremburg, Ring stuff (Rhinegold, Sigfried, Valkyrie, Twilight of the Gods), Lohengrin
Chopin- various stuff, preludes, Fantasie Impromptu, etc...
Richard Strauss- Till Eulenspiegel's merry pranks, Thus Spake Zarathustra,
Marcello- Oboe concerto Dm
Bach- hmm, whatever I have lying around
There's probably more on some anthology CD's I listen to all the time, but that covers the major composers.