The Options section sets up operational values:

SourceFieldWhich field is defined as the Source address field
AssociateTypesThe types of associates that make up the office. This is used in Week @ a Glance to display groups of associates and in billing to specify rates.
TTDOptionsOptions to display in the subject line of Things to Do.
HistoricalTTDLimitThings To Do will not be created if older than this number of days.
FYIEnabledEnable the FYI support.
EnvelopeNoSenderIf set false, the office address will be used as the sender text for envelopes.
AddressTemplateDefines the template to use when using Keyboard Shortcuts Ctrl-B and Ctrl-2.