I've been looking in to why my n64 looks like gack when I hook it up to my 65" plasma tv directly, or run it through my reciever (aventage Yamaha 2010), and I've found out various things: the N64 puts out 240 video, it'll look best on a old-fashioned tv, due to scanlines and the fact that said tv will do 480 at best. Plasma and LED tv's don't have scanlines, and they don't really like 240 video.
So--- apart from trying to do an RGB mod on my N64, here's what I propose: Lenkeng 363 box, taking the output of the n64, then through my Oppo Blu Ray player which does have HDMI input, then through the reciever to my TV. Very Complicated, I know, but I don't see any other way to do it right now (Unless someone invents an N64 that puts out HDMI, which isn't going to happen, at least not yet)
thanks ! I may wind up going "your route" and get Windows on my Mac Pro, then get the emulator. That seems a more possible (maybe cheaper) solution in the end. So much for playing Conker's Bad Fur Day on my new Plasma tv. :/ a 3d0 looks great, but N64? nope.