110v 220v do it work?

The zener diode you reference has a zener-voltage of 5.1V and a power rating of 1W. You want to place a resistor in series with the 9V source and the zener diode to limit current draw.

The datasheet for the IN4733 states that at a zener current of 49mA the zener voltage is at the rated 5.1V. The only calculation you need to do is to size the resistor such that you have at least 49mA, although lower current would also likely give you around the 5.1V zener rating. Normally you would look at the datasheet for a chart to give you this information, but the one I found left this information out.

$$ R = \frac{9-5.1}{10mA} = 390 \Omega$$

But, again, larger sized resistors are likely to give you the voltage you want with lower power dissipation. Test to verify.

As Mike DeSimone points out, your battery can't produce 3.8 V and 1.2 A at the same time.

But even if it did, that would only be about 4.6 W.

You want to use it to power something with 5 V and 2 A. That's 10 W.

You can't do this without first overturning the entirety of conventional physics by disproving conservation of energy.