re: the placement of "do" in a question.
Closed questions demand an answer of
yes/no,
true/false or
right/wrong.
For example:
Question: Does she an English book?
Answer: Yes, she has an English book.
Question: Do you want to go to the store?
Answer: No, I don't want to go to the store.
Object Questions ask about the object of a sentence. The question requires the use of the auxiliary verb 'to do'.
Question: Which train did you catch?
Answer: I caught the train to Boston.
Question: What movie did you see yesterday?
Answer: I saw a film called 'Pulp Fiction' yesterday (on DVD).
for further explaination see: "Forming Questions"