Is there anything unusual about Northumberland and Durham registers?
Yes, you will find that the registers for 1798 to 1812 are particularly helpful in your researches. The Bishop of Durham, Shute Barrington, gave detailed orders to the parishes in his Diocese (ie County Durham, most of Northumberland, and Alston in Cumberland)) to include a lot of extra information. Baptism entries, in particular, contain extra details which help immensely.
