If it's running XP, OE will already be installed, and you can copy the account settings (and your address book) from those on your desktop. To export the address book, just run OE on the desktop and choose File/Export/Addressbook.
To export the account settings, click Tools/Accounts, highlight the mail account and choose Export. If you export both to a memory stick, you just need to reverse the process (i.e, import) onto you laptop.
The other change that you will probably want to make is Accounts, select the mail account, choose properties, go to the advanced tab, and check "leave a copy of messages on the server). That way you can collect all mail on both machines.
If the Laptop is running Windows 7, you can't install OE, but can install Windows Live Mail (which is really just OE with a few changes).
http://windows.microsoft.com/en-GB/windows-live/essentials-other-programs