Ah Goldeneye, it was the first game I bought once I got my N64. Loved that game so much. But sadly it has not aged well. Last Thanksgiving, my cousins and I dug out the cartridge and played. It was fun in a nostalgic sense, but the game mechanics were foreign to me now. And it's clunky and way harder to aim then modern console shooters.
I still have very fond memories playing Goldeneye, but I won't be replaying it again. That being said, I still love playing a few 64 games. Smash Bros, Mario Kart, and Mario Party are all still as fun today as they were 15 years ago. I feel that is a testament to a well made game and system. The fact my 64 is still working without issue after all these years is something new consoles could learn from *coughred-ringcough*
I also still play my original xbox games on rare occasions. I played through the entire MQ of Morrowind leading up to Skyrim's launch in 2011, after a brief re-adjustment to the play style I had a great time. I also still play some Splinter Cell Chaos Theory levels, the best game of that franchise imo. Oh and I still really enjoy playing Pirates of Caribbean, even thought it's not b/c on the 360 and I have to actually plug in my old xbox. And the game is still buggy and corrupts save files. lol I still like it though.
I feel you can go back and enjoy some old games, some are still fun to play, others are best left to memory. I would just say, go back cautiously and don't force yourself to play and old game and risk ruining the fond memories.