The Airbus planes have a feature where the GPWS can be disabled. But I cannot find any switch in the 737NG cockpit to disable the GPWS.
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:
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.