To import from OE.

In Thunderbird Open Address Book Tools > Import select 'Address Books' and click on Next select 'Outlook Express' and click on Next' You may need to map the OE files to Thunderbird address book fields.

Alternative option:

Export the OE address book as a .csv file.

In thunderbird Open Address Book Tools > Import select 'Address Books' and click on Next select 'Text files' and click on Next

Locate the .csv file and click on Open You will need to map all the OE files to Thunderbird address book fields.

I don't understand about mapping files to address book fields. This is over my head - please explain!

AS an example: the data stored in OE might have a field called 'Surname', In thunderbird that field would be called 'Last Name'.

so you would need to select : 'Address book field' Last name' = record data to import 'Surname'.

However, it is often more useful to edit the .csv file before importing. You can open a .csv file usingeg: MS Excel

Thunderbird stores info in specific fields. It does not use a single field called 'Name', so if you current have just one field/column header for the Name, then it would make life much easier if you edited the column headers to say 'First name' and 'Last Name'. Thus dividing up the Name into two separate columns.

This link will tell you all the current standard Thunderbird field names and the order they are in, so you can match your .csv file to say the same in it's column headers. http://kb.mozillazine.org/Import_address_list_from_text_file

If you edit the .csv file and then save it. when you want to import the .csv file info, it will look like the image below, otherwise the 'Record data to import' column will show the OE fields you currently use and you need to map them to the respective Thunderbird field. you use the 'Move' up' or 'Move down' buttons to help align.

In other words, I can't do a "cut and paste" from OE to Thunderbird; I have to re-enter the information? Also, can I cut and paste an entire directory with all its contents?

There is no cut and paste. Simply not possible. There are some modifications you can make to Thunderbird to use the windows address book. See http://thunderbirdtweaks.blogspot.com.au/2013/12/windows-contacts.html

Note that the windows address book is stored in a WAB file and you will need to move that to any new computer as it is not part of Thunderbird. Later versions of Windows make importing it to the contacts folder in windows very simple point and click action.