It appears that you will have to do a little work to export all your T-Bird mail to M$ Outlook. After reading the above link, it looks to me like the easiest way is to install the T-Bird MBOI/Import/Export add-on: https://nic-nac-project.de/~kaosmos/mboximport-en.html
to your existing T-Bird install (the one where all the mail is located). Then re-open T-Bird, and you'll see a new entry under Tools=>Import/Export in mbox/eml format=>Export all messages in this folder (you should have the folder to be exported open before starting the exporter)=>you will be asked where to save the exported mail=>choose a place to save the exported mail, creating a new folder for each folder to be exported. The exported eml folders/files will have to be manually copied to a place where you can access them with outlook express - i.e., you may have to burn them to a CD, or (this is wierd) e-mail the folders to yourself as attachments (which could get ugly, depending on the size of the folders/eml files).
Once you are able to successfully convert the T-Bird mbox-format mail files to eml, you will have to manually copy them to outlook express (from the mozillazine link above):
create EML files and then drag and drop them into Outlook Express (plain Outlook won't work).