Hi.
I've contacted the NVC and they said they sent me the immigration visa processing fee bill two weeks ago.I have two questions I hope somebody will help me with.
1) After I send them the money and they send me the instraction packet with the required papers and the form DS.230, will I have to send it pack to them with all the papers or I'll have to take it with me to the Interview ?
2)what kind of questions they ask in the interview and how long does it take ?
any help will be appreciated .thank you so much.

Try the following link - it is very useful - it will give you all the details you need. Just remember to not send in anything without your notices and to make sure your case number from the NVC is at the top of each and every piece of paper submitted.

http://travel.state.gov/visa/immigrants/info/info_3176.html

In the drop down list you will select your country's consulate. Good luck and hope this helps - I know it helped me!

Yea every country is diffirent like for cuba when you recive the Info pack after paying the IV Fee bill you get a coverletter that you need to return with the documents they dont send you the acctual DS-230 they send you get a paper that tells you to go to the website listed above and pick your country and then there it tells you what to do.