there's no best settings, it all depends on individual preference.
Ibanez's factory action is 1.7mm for the topmost string, 1.5mm for the smallest string. Measured at the 12th fret.
For me, I prefer about 1.25mm and 1mm respectively. I like my action relatively low.
I read somewhere that Richie Sambora (Bon Jovi) uses low action when recording, but high action (2mm+) when playing live.