The screen shot mentions those are default forms for certain ticket classifications in that app. You'd have to change the default forms for those classifications to another form that you configured to make tickets with those classifications if you want to delete the old forms.
You can edit which forms are used by the default classifications from the main TDAdmin page of the ticket app under its Forms section. There is a button at the top of the Forms page to edit the default forms.
Sr Support Consultant, CS