For the Saint-Saens, try to hear also Levine and the Berlin Philharmonic, or the CD (I've heard the SACD isn't very good) of Munch's recording on RCA (which has one or two edit errors in it, especially a long organ note in the second movement missing the first half of the note! But the music making is terrific).
Thanks; I'll have to check that out. I'm not even sure the Von Karajan version is on CD; I had heard it from an LP (Deutsche Grammaphon) back in the early 80's. If I recall, it was a simultaneous recording of the BPO in Berlin, and the organist in the Cathedral of Notre Dame in France; pretty high tech for that time.