" ... when I go to Reports > Unpaid Invoices > Print ....".
There is no "Unpaid Invoices" choice in the Quicken Reports dropdown menu.
The path to Unpaid Invoices is: Business > Unpaid Invoices.
When Unpaid Invoices are displayed and you click "Print", you get a dropdown with the three choices you noted: "List, Invoice, Statement".
You say, "I want the list": so why are you not clicking on "List"?
When you click "List", you will get the standard Quicken "Print" dialog, which includes a dropdown to "Export to:". In that "Export to" dropdown, you can elect to create a "tab delimited (Excel compatible) disk file".
When you have created that tab-delimited .TXT file, you can run Excel and tell Excel to "Open" that .TXT file. Excel will walk you through the rest.