Voltage Conversion from 220V to 5V
The best circuit to use is a small transformer, as it has isolation between the mains supply and you.

How about simply a resistive voltage divider? It has the benefit of simplicity, a reasonably low output impedance to drive the ADC, and a well specified and calculable input voltage withstanding, if you read the data sheets for the components you use.

You could put an LT1006 after the voltage divider if you want to. It depends what your ADC input looks like, whether it needs a lower impedance than is feasible with a resistive divider.