Nintendo sixty fourrrrrrrrrrrr.
I didn't own either. My best friend owned N64 -> Xbox in the same time period I owned PS1 -> PS2.
Based on this, I played Goldeneye & MK64 a lot at his house on N64; and Halo 2 a lot on Xbox. That's two games to one, so N64 wins :P
(Also went back to play a few of the classics on virtual console helps too :P)