Ues, form builder 2 completely replaces the previous versions of UE4 , DFP, Validation Toolkit and HTML Editor.
In addition to the integration of the tools in the FB Wizard, you will still have the standalone server behaviors for each that can be used to manage your pre existing pages.
uninstall any of these extensions that you may have installed:
Form Builder 1 /
Validation Toolkit
Digital File Pro
Universal Email
HTML Editor
iRite
prior to installing form builder 2.