I don't follow, do you mean the button that says something to the effect, "Do you want to prevent your system from going into Standby in the future?" ?
If you click yes, it changes those two values to something like 2 and 512 (if I remember correctly) which triggers removal of Standby from the options in the shutdown dialog. Restoring these values will return the standby option.
Again, this is one of those asinine undocumented "features" of Windows...I had to find an old copy of the registry, restore it, and use some context clues to find where this information might be stored in the registry. Then swap back the registry and compare values. I've since needed to apply it to several machines and can indeed confirm that it works.
Best regards,
Floyd