Well, first of all SAM is a registry hive not a folder.
Secondly, I understand that the SYSTEM account is the only one which has the
right to read the SAM hive.
It seems that you are in for a lot of work.
Jim
The SAM contains "hashes" of user password that can not be decrypted. There
are free and not free programs that can help you find passwords that
correspond to the hashes such as the free Cain and Abel. You may not be able
to recover strong passwords however.