Ladies and gentleman Save
You address a woman as Mrs. when you know she is married. When you know she is single you address her as Miss. When you are uncertain about her marital status it is best to address her as Ms.
The proper way to address that letter would be "Mr. and Mrs. John Doe."
If this is a personal letter to just this individual then you would address it: Mrs. Jane Doe or you could put Mrs. John Doe.Some women would find it offensive to call them by their husbands full name and just forgetting theirs altogether so address it Mrs. Jane Doe.
Govenor and Mrs. Beebe
The best way to address your letter to a Minister is to Reverend and Mrs. _______
To;The Reverend and Mrs (Insert name)
Captain and Mrs.....
Dear (Mr. / Mrs.) XX
When addressing an envelope to the wife of a doctor who is not a doctor herself then and he is Dr. John Doe, then address the envelope to her as Mrs. John Doe or Ms. (Mrs.) Jane Doe.
The same as you normally would. Her status is still Mrs. ?
If this is a formal letter, you address him by his rank.For instance, if he is a private:Dear Private and Mrs. Smith.Likewise if he is a Colonel:Dear Colonel and Mrs. Smith.
The President and Mrs. Bush The White House Washington, DC 20500