Question : Stop: c0000218 {Registry File Failure} \systemroot\system32\config\SECURITY

I have a Dell Latitude E6400 with Windows XP Pro.

Get the following blue screen error:

Stop: c0000218 {Registry File Failure}
The registry cannot load the hive (file):
\systemroot\system32\config\SECURITY
or its log or alternate.
It is corrupt, absent, or not writable.

Beginning dump of physical memory
physical memory dump complete.
Contact your system administrator or technical support group for further
assistance.

Did the following to try to resolve
Booted from CD to recovery console

md tmp
copy C:\windows\system32\config\security C:\windows\tmp\system.bak
delete C:\windows\system32\config\security
copy C:\windows\repair\security C:\windows\system32\config\security

It does not blue screen but it gives a repetitive security error that is too fast to see but I don't know how to stop to acknowledge.
Putting the original file back restores the not so pretty shade of blue and original message.

chkdsk /r did repair some files.

Thank you for your assistance.
Best Regards.

Answer : Stop: c0000218 {Registry File Failure} \systemroot\system32\config\SECURITY

check if some
can execute the following  in toad
alter session set NLS_NUMERIC_CHARACTERS='.,'
/
and repeat
select to_number('123.45') from dual;

in your sqlpus you mention to_char instead of to_number : that is a different query
behaviour can be different for the same query as
sqlplus looks for a login.sql prior to connect and in that file settings as above can be changed

check your registry for NLS_SETTINGS that might be changed by your XE installation
for example
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ORACLE\KEY_XE
and check the same for toad