Oh yes!  I do backup my Outlook Express folders as well as my address book. I just did that a couple of days ago actually. 

When I save my Outlook Express folders I do the following:

• show my hidden files,
• go to "Documents and Settings". Find my profile,
• click on "Local Settings",
• click "Identities"
• click the next folder with the long string of numbers/letters
• save the Microsoft folder

After an install I just copy / paste it back.

When I save my Outlook Express address book, I do the following:

• do the above  to get to your profile
• click "Application Data"
• click "Microsoft"
• click "Address Book"
• Save all files from in there

After a reinstall just copy / paste it back. No need to get confused with the import / export stuff.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi