What is "Black stabilization" and which level should I choose?

This setting is to provide better picture performance if user’s screen are mostly dark scenes. If no special needs(ex: playing shooting games in dark scenes), it is suggested to turn off.

How to set power lock and menu lock?

On some monitors, there is a power button lock that locks the power and power button in the ON position.  There is also a menu lock feature which can lock and unlock the OSD (On-Screen Display) Menu.  Power Lock: To lock the Power Button press and hold both the [1] button and the down arrow button for 10 seconds.  OSD Lock: ...