51
How Many Kings And Queens Of England Have There Been?
With the exception of Empress Mathilda and Lady Jane Grey who reigned only few days. There are six real Queens who ruled England - Mary I (Bloody Mary Tudor), Elizabeth I (Tudor), Mary II (Stuart), Anne (Stuart), Victoria (Saxe-Coburg-Gotha) and the present Queen, Elizabeth II (Windsor)
8
I believe there's been 51 (since William the Conqueror, 1066 - 1087, to Elizabeth II, 1953 - present).