Hello... I will give you my 2¢ ..I think that your confused about "terms" This is how it can be done ...
1. At times "PC" manufacture's will build in a hidden partition ( can't be seen unless you know how to access it) One other... They include a "Recovery partition" that you can see. Both can be accessed from within Windows and restore your OS to original factory condition using Windows
2. If neither of these are present ..there is another way... You use "Windows Backup and Recovery" You create the Image ...also run from within windows
3. One other way is to use an "Elevated Command Prompt".... sfc /scannow (system file checker) it will repair any corrupt OS files ...
4. Bottom line ... Windows 7 needs to have the "Factory Image" to recover the PC to original factory condition ...Either you have one that came with the OS (PC) or you have to create one ... That's it you can't recover to original factory, if you don't have one or the other.
5. System Restore .. Is another to recover your "Registry" to a time before you messed things up. Will not recover to original factory..if you really messed up.
Hope this helps you in some way... Regards Fred