Open the Registry Editor by hitting Start and typing “regedit.”
Unfortunately, the items populating your context menu are not all located in the same place in the Registry.
You can find most of the context menu items used for both files and folders by drilling down to one of the following keys in the navigation pane on the left:
HKEY_CLASSES_ROOT\*\shell
HKEY_CLASSES_ROOT\*\shellex\ContextMenuHandlers