Kondo is legendary. He's easily my favorite composer.
Not only do his melodies stay on my mind forever, but he can write for any style of music and do so very competently. It's really hard for me to rate which of Kondo's pieces is my favorite because it depends on how I'm feeling at any given moment.
I also like when his stuff is arranged. This is when it really, truly shines. Kondo did most of his composing on the limitations of the NES, SNES, and N64 and I find it nice when his stuff gets the live band and/or orchestral treatment that it deserves.
My favorite arranged album is Super Mario World - expertly arranged and featuring Kondo's favorite saxophonist - it's absolutely amazing.
I just wish he'd get back to composing. Screw all this supervisor shit. I want Kondo back in the lab composing the entirety of the next Zelda or Mario game.