1)Auto-Distortion Control in Camera and Lens Corrections Works only on raw files and Only with Nikkor lenses The new camera bodies can set this to ON automatically The older bodies don't have this feature and you must turn it on for each file processed, could be done as a batched setting process. Makes adjustments based on the lens focal length and characteristics at that zoom setting
2)Distortion Control as an edit step Works on any file type Simple barrel/pincushion effect Can't adjust for complex distortion
Don't forget that you can also selectively compensate for the vignette of the lens at that focal length and aperture. This is not something you can set in the camera but must be applied to the raw file manually.