How to force refresh or delete the DISPLAY key on Win7 ?

Hi System Experts:

I need to refresh the monitors recorded by my system (Win7) in the registry; I have a long list of monitors under:

HKLM\System\CurrentControlSet\Enum\DISPLAY\

I was trying to delete this key and restart the system to get the monitor list re-populated, but the system does not allow me to delete this key.

Is there a way to either force this key re-freshed to show only my currently connected monitors? Or delete this key all together is fine too.

I have a feeling that I might have to write a program to do this ?

Thanks in advance.

Polaris