Assuming your emails are in Local Folders:
in Outlook Express, you can go
File > Export > Messages > OK > All Folders
this will export all your messages to the pst file Outlook XP is using.
By default it is
C:\Documents and Settings\jtk\Local Settings\Application Data\Microsoft\Outlook\Personal Folders.pst
(unless you have configured Outlook differently).
Now copy the pst to a CDRW and take it with you to the office.
At office Open Outlook
File > Import & Export > Import from another program or file > Personal folder file (pst) > Browse for your pst file and select the folders you want to import.
