A Mahler symphony, preferably one of the "Wunderhorn" symphonies (2,3,4). I'm open to suggestion with respect to performances. Klemperer maybe for 2? Kletzki for 4? Bernstein for 3 (if good sound can be obtained)?
Bruckner 4 - perhaps the Bohm version (I'd actually prefer the 8th symphony, but my favorite performance, the Karajan with the VPO, is a digital recording.
Schubert - the Great C Major symphony - how about Krips on Decca?
Saint-Saens Organ symphony - yep it is a blockbuster. Can't say I have a favorite recording - the Munch tape used to go for mucho dinero.
Tchaikovsky Symphony 5 - well, not the greatest symphony, but the Mravinksy recording is an incredible reading - intense, subjective and well executed.
Fun.