msconfig won't run

Blocked at the very first step! Start>Run>msconfig

operating system is WindowsXP media edition
computer is Toshiba Satellite A105-S4084
used in a home setting with no networking

when I run:

Start>Run>msconfig

nothing happens. Nothing happens, either, if I run:

Start>Run>regedit.exe

If I run:

Start>Run>cmd

a terminal window briefly flashes on the screen but then immediately disappears. Running Sys Internals Process Explorer also flashes a window on the screen that immediately disappears. I have tried to use the RegWorks registry editor to change the registry values, but the changes are not saved when I exit the program. CCleaner will not run, it, too, flashes a window on the screen.

I attempted to do the fixme.reg change to the rfegistry as described in the thread Msconfig:

REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\MSCONFIG.EXE]
@="C:\\WINDOWS\\PCHealth\\helpctr\\Binaries\\MSCONFIG.EXE"

Which briefly flashed on the screen the error message (I had to run it several times to get the message read):

"Registry editing disabled by your administrator"

But control panel>user accounts reports that the account I am signed in on is an administrator.

System Restore in MyComputer>properties has the "Turn off System Restore (disabled by Group Policy)" checkbox checked and greyed out.

I am truly stuck, and this being my girlfriend's computer, facing a HUGE credibility problem.

 

further information

I have been further exploring and got to Control Panel>Administrative Tools with the following results. When I click on:

Local Security Policy (C:\Windows\system32\sepol.msc)
Component Services (C:\Windows\system32\Com\comexp.msc)
Services ((C:\Windows\system32\services.msc)
Computer Management (C:\Windows\system32\compmgmt.msc) or
Performance (C:\Windows\system32\perfmon.msc)

a window briefly flashes on the screen and then disappears too quickly to read.