The problem is that you did this while logged on as the Admin. Now, since the Admin created those files (as far as Win XP is concerned) the Admin account is the owner. By default your user (unless an admin him/herself) would not have full access to the files - including the Outlook pst files you moved over.
Check the file/folder permissions/security/ownership. I'll bet the Admin account has ownership and is the only account with full permissions.
As admin, add the user account to the folders/file (*just to folders and allow propagation to child objects if they contain many files) and give them "full" permissions. Then go in as the user and take ownership.
I have seen this happen before.