What EQ preset/setting used is subjective, and entirely based on the 'ear' of the listener. The quality of the output of your sound card and speakers effects things too. There is no 'best' setting on the EQ, as you asked.
Anyway, refer to the Equalizer Q&A Guide
for questions re: presets and settings.
I've also answered your other question in the Removing duplicate songs
thread that you started.