Little bit of everything.
I like 70s rock, or anything that has that sonority. Prog would be mandatory, like Yes or Genesis.
Some good pop music also adds diversity, like dB's, Wilco, etc.
Jazz, I prefer 60s/70s than 50s. Electric jazz, even better. I'm not a fan of the traditional kind of jazz recording, with the heavy panning.
For classical music, I'd use some Mahler, Holst "Planets", and maybe some russian thing, Prokofiev, etc, but I'm still learing about this stuff.
Some funk and soul would be in order too, Marvin Gaye, James Brown...
alexandre