fill in the blank

Henry IV of france was a member of the family or house of _____________ which now became the rulng dynasty of france.

is it planganet?

The Plantagents were English.

http://en.wikipedia.org/wiki/Henry_IV_of_France

so bourbon?

To find the answer to your question, we can start by doing a quick search. You are correct that Henry IV of France was a member of a ruling dynasty. However, the correct term is "House of Bourbon," not "Planganet." The House of Bourbon became the ruling dynasty of France with Henry IV's ascension to the throne in 1589.