The account settings are buried deep in the registry.
You can load the old user hive from the USB disk, export the account settings keys and then import them into your live registry.
Open registry editor: click start, click
Load hive and open
D:\Documents and Settings\Jules\ntuser.dat, depending on the drive letter and path to your user profile on the USB disk.
You should then be able to highlight and export the key
Software\Microsoft\Internet Account Manager using
Export from the loaded hive and highlight and import them back into
HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager using
Emails should be stored in the following folder on your USB disk.
D:\Documents and Settings\**username**\Local Settings\Application Data\Identities\**identity**\Microsoft\Outlook Express, again depending on the drive letter and path to your old user profile.
Simply copy this folder across to your C: drive. You may want to rename the existing folder just to be on the safe side.
disclaimer - you can seriously screw your computer up by messing with the registry. always take backups of keys before making changes, using the file | export option inside registry editor