I have my SNES connected to my HDTV using GCN composite cables, and it looks pretty good. If I recall, SNES, N64, and GCN can all use the same composite cables.
with that thing you plug in the back of the controller to put your gameboy game in? that was awesome. pokemon stadium was the first thing that made me feel like i was using real pokemon like the cartoon. pokemon puzzle league was cool too. gay...but cool