windows failed to load because the system registry file is missing, or corrupt

hi
first off im a newb im not very good at this hence my problem

its an HP g6000 nothing modified.... other than a new screen due to breaking 3 years ago

ok so i decided to turn my old laptop on that for some reason (i cant remember) stopped working 2 years ago
ive decided to use it as a basic home system

it came on and went straight to windows boot manager giving me a 3 step solution to a problem

1. insert windows installation disc and restart computer.
2. choose language settings and the click next.
3 click repair your computer.

file: \windows\system32\config\system

status: 0xc0000225

info: windows failed to load because the system registry file is missing, or corrupt.


i dont know what this means but i dont have the install disc so i got an iso online and put it on to a 8gb flash (previously using rufus)

ive plugged it in and nothing happens just goes back to error and same 3 steps

please help

ive now made a boot disc which is also failing to work..

Please follow these steps to recover the registry. Manually Restore the Registry From its Backup in Windows (Windows 7 / Vista) - Sysnative Forums

when i try to access the sytem recovery through advanced boot options it doesnt list the option to "repair your computer" every other option is available. i tried safe mode with command prompt and it takes me back to original issue 0xc0000225

you have to restore the registry backup. follow all of the steps.