NTSC games played with this setting off will result in the top part and lower part of the screen not being clipped, which can look weird. This option opens the Palette Console. The Palette console allows you to load a different palette, modify a palette, save a palette etc. You can choose from the ones that come with NESten or you can create one yourself. Should always be on unless you have a very slow computer or a hearing disability.
Buffers Changes the sound buffering numbers.
Useful if you're bored, or if a particular channel sounds strange and you want to submit a bug report. You can log any NES tune to WAV with this option on. Be warned, however, 44100Hz 8 bit mono WAVs do take up a bit of space. Time to break out the MP3 encoder. Player 1 input Allows you to select the keyboard or joystick controls and configure them for player 1.