I think the type of TV matters for old games too. I have a plasma TV, and old games look much better on it than they do on any LCD screen. There are several reasons for this, as a plasma has more similarities to a CRT with its glass screen, great contrast, deep black levels, etc. It also has much less latency than LCD, so no perceptible controller lag. Adjusting things like the sharpness level on a game-to-game basis can also help.
While any good-quality flat-screen CRT will always be best for old games (which I still have and sometime use), SNES and N64 games still look surprisingly decent on my plasma, enough that I often play them there for convenience. Plus, the select few N64 games that support widescreen look quite nice in 16:9. NES remains crap on it, though.