If you used the backup software that came w/ the HD to make the copy, it should all restore through the software. 

Macro Solution:  copy c:\documents and settings\~ from the USB drive to the local

If it's just a copy you will have to go to  (on both local & USB drives)
<drive letter>:documents and settings<user name>
highlight  your folder, and go to the tools dropdown, select folder options, view tab

in the list that shows, hidden files and folders , select "show hidden files and folders"
OK out until you are back in the file browser

your playlists and such should show up in
<drive letter>::Documents and Settings<user name>Application DataMicrosoftMedia Player
on the USB, so you can copy them from USB to Local

your music files will be in

<drive letter>:documents and settings<user name>\My DocumentsMy Music