How to disable GPWS in a 737NG just like how the Airbus can?
There is no way to totally inhibit GPWS on the B737 except by pulling the circuit breaker.  

What you can do is inhibit specific modes of the GPWS. This is done via the following switches:   


Source: Boeing Co.

The Below G/S switch (1) inhibits the below glide slope alerting.
Flap and Gear inhibit switches (4 and 5) allow inhibiting the "Too Low Flaps" and "Too Low Gear" alerts.
The TERR inhibit switch (6) inhibits the look-ahead terrain alerts and the terrain display on the ND.