I've been hooked on Mahler for decades.
The first set of LPs I got were by Solti, so to a large extent I learnt them all in his interpretation, and as we all know, teenagers are impressionable, and his way has become for me in many ways the right way.
That being said, I will admit a soft spot for Bernstein. His romantic way with the slow movements seems right--to me at least.
Then there are a number of other conductors' individual versions of symphonies that are great.
I'll pull out my favs and post a list later.