Importing old emails from/to Entourage

Let me just say, I have very little experience with Macs. I had to reload the OS (9.0) and everything on a G4. Loading and configuring everything went ok. However, the options to import the old emails into Entourage do NOT include an option to import from Entourage email format!?! There are options for Outlook Express, Eudora, etc… and CSV files, but none of those work when I point them to the file which I am pretty sure is her old email (I think it was “Messages”) This is the version of Entourage that comes with Office 2001 for Macs

Any ideas? I feel like I am missing something simple…..

(I have not updated the OS or Office, yet. Perhaps when I service pack Office