Goldeneye was the best game on the 64, hands down (one of the best games to ever be made from a movie). Personally, I like CoD 4 + 5, and Unreal Tournament 3... I would argue that UT3 is better than any halo game i have played... then again, halo never really made anything new... few new weapons here and there, but its the same thing 3 times over. (they even had alot of the same maps in 2 as the original...)
Counter Strike 1.5 is by far my favorite. the feeling of it and the models + sounds are just perfect. Counter strike source is in the top for me with the ragdolls and graphics of the maps. The weapons however is really ugly