Is there a way to export a list of all pages and files?
You can use Views Data Export


  This module is designed to provide a way to export large amounts of
  data from views. It provides a display plugin that can rendered
  progressively in a batch. Style plugins are included that support
  exporting in the following types:
  
  
  CSV
  Microsoft XLS (or really simple HTML understood by Excel)
  Microsoft DOC
  Basic TXT
  XML
  


and export as CSV. I recommend you watch this video tutorial.

Your client can then view the CSV file in Excel.