The question is based on the premise that the monarch of England is simply determined by applying a set of defined rules - i.e. legitimate, male line succession. As argued by others above, this has always in practice been combined with a degree of pragmatism (i.e. who is the best ruler) and even an element of democracy (as shown by the Act of Settlement) not to mention brute force. It's also highly debateable whether 1066 is the most appropriate starting point (why not King Alfred the Great?). However, ignoring those elements, I've had a go at applying the rules of succession to William the Conqueror's descendents below.
The somewhat surprising conclusion is notwithstanding the various immediate breaks in succession, the lines tend back to the line that had the throne, largely due to judicious use of marriage, imprisonment and execution! The only exception is the Jacobite claim, which is technically with Franz, Duke of Bavaria, although this line has never claimed the throne of England.
Here is the full list, with the dates that the people would have technically claimed the throne:
William the Conqueror - 1066-1087
Robert Curthose of Normandy - 1087-1134
Henry Beauclerc - 1134-1135
Matilda of England - 1135-1167
Henry Plantagenet - 1167-1189
Richard the Lionheart - 1189-1199
Arthur of Brittany - 1199-1202
Eleanor of Brittany - 1202-1241
Henry of Winchester (III of England) - 1241-1272
Edward Longshanks (I of England) - 1272-1307
Edward of Caernarfon (II of England) - 1307-1327
Edward III - 1327-1377
Richard II - 1377-1400
Edmund Mortimer - 1400-1425
Richard of York - 1425-1460
Edward IV - 1460-1483
Edward V - 1483-1483 (assuming we ignore the fact that parliament declared him illegitimate?)
Elizabeth of York - 1483-1503
Henry VIII - 1503-1547
Edward VI - 1547-1553
Mary I - 1553-1558
Elizabeth I - 1558-1603
James I - 1603-1625
Charles I - 1625-1649
Charles II - 1649-1685
James II - 1685-1701
For the following line, see http://en.wikipedia.org/wiki/Jacobite_succession
James Stuart (Old Pretender) - 1701-1766
Bonnie Prince Charlie - 1766-1788
Henry Benedict Stuart - 1788-1807
Charles Emmanuel IV of Sardinia - 1807-1819
Victor Emmanuel I of Sardinia - 1819-1824
Maria Beatrice of Savoy - 1824-1840
Francis V Duke of Modena - 1840-1875
Maria Theresia of Austria-Este - 1875-1919
Rupprecht of Bavaria - 1919-1955
Albreacht of Bavaria - 1955-1996
Franz Duke of Bavaria - 1996-present.