Windows Contacts and Windows Mail Contacts are the same thing. The
difference is just semantics. Windows contacts are a separate application
from Office and intended for the vast number of home users who will never
need to purchase nor use the Office system.
Everything depends upon what you mean by "integrate." The way this can be
done by a user who has Office Outlook installed is: 1) They can choose to
only use the Office Outlook application for both work and personal email
contacts together. Or, 2) On the same machine, they can run their personal
email account and contacts through Windows Mail and run their work related
email and contacts through Outlook. Some would define either of these 2
options to be "integrated."
-THP