If both the father's and mother's names are incorrect, it could be a cousin or someone completely unrelated, especially with a name like John BULL.
The film you reference sounds like it is a parish record from FamilySearch.org. If you can't find the information on that site, go to your local Latter Day Saints (Mormon) family history centre and ask to rent the film.
If you post all of the information you have about your ancestor on the appropriate location board, someone will most likely point you to the available parish register resources for that location.