Next on the list for Mahler....

The Mahler Symphony No. 3 that Slipknot mentions would be my recommendation for your next experience with Mahler. After that, I'd recommend you listen to the Sym No. 8 and then the No. 6. Recommendations for these are:

Sym No. 3: Horenstein/LSO, Nonesuch (originally issued on Unicorn)

Sym No. 8: Solti/CSO, Decca/London

Sym No. 6: Horentstein/StockholmSO, Nonesuch | or Solti/CSO Decca/London.

Each of the recommendations above are excellent performances with very good sonics.

The most famous Mahler Symphonies are probably Nos. 2 and 8. The most accessible are probably Nos. 1 and 3. For the Symphony No. 2, it's hard to go wrong with Solti/LPO on Decca/London (which I find preferable to the Mehta and several others).

Good luck in your explorations!
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Audphile1, for the Mahler Symphony No. 1 on vinyl, I can recommend the Horenstein/LSO performance on Unicorn RHS 301 (also reissued on Nonesuch, I believe), and the Solti/LSO performance on Decca SXL 6113 (Speakers Corner reissue) that you referenced in your post. These are very different performances, both good and in good sound.
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