You should check out the Anonymizer extension.
A word of warning - make sure that outgoing email is disabled! You don't want any of your CiviRules etc. being triggered and sending out emails. I saw a colleague who had CiviCRM WordPress Profile Sync installed, which meant that changing the email address in Civi changed the email in WordPress - which sent ...
Are you referring to the suffixes drop down, Jr. Sn etc? if so…
You have full control of the list of suffixes:
From the CiviCRM menu –
Administer > Customize Data and Screens > Dropdown Options > Individual Suffixes
From here, you can add, update and edit any of the options.