Options dialog - DNS - Data Files
(Main window -> Options button -> DNS / Data Files section)

Simple DNS Plus v. 5.0
Copyright © 1999-2008 JH Software ApS
Location of DNS data files (zone files)
Specify the directory where data files are stored.
The default is the "ZoneFiles" directory under the Simple DNS Plus data directory:
Windows Vista/2008: C:\ProgramData\JH Software\Simple DNS Plus
Earlier Windows versions: C:\Documents and Settings\All Users\Application Data\JH Software\Simple DNS Plus

 

Defer loading individual zones until first request (load on demand)
In setups with many zones this can greatly improve the server startup time.
Inactive zones will never be loaded, which may also improve memory usage.

 

When loading zones from disk, enforce a minimum DNS record TTL value
Replace lower DNS record TTL values when loading DNS zones.