I don't think Ann Munroe and Anna Mertaugh are the same person. Do you know if Mundo's parents came with him to America? Perhaps you could find their death records on ScotlandsPeople if they stayed in Scotland. The death records contain the spouse's maiden name, as well as the parent's names.
Were you able to look at the death, cemetery and funeral records for your family on the Saratoga GenWeb site?If you didn't, scroll down to the search engine button, and click, then type Urquhart into the search engine field. I think the cemetery name was Greenridge???