Pop,
In OE, go to File, Import, Messages.
Choose Microsoft Outlook Express 6 (unless you know you were using 4).
Then Next and select Import Mail from an OE6 store directory.
Specify the location of the .DBX files that you want to import.
It should be quite straightforward - I've done it several times myself.
Of course if the backups that you made were not of the right OE identity, then you may simply not have the files any more.
SD