Hi Kashif
You said you came in the UK in 2004, did you have a student visa? If so, when did your student visaa expire? Was it before you get married or after? If it is after you got married, it means that from 2004 to 2009, you had 5 years continuous legal stay in the UK, therefore you can apply for your permanent residence known as ILR (ILR:indefinite leave to remain). Before you do so, make sure you pass the life in the UK test.
It is only after you have spent one year on your ILR document that you can naturalize as a British citizen. If you need further information, contact your nearest Citizen Advice Bureau, the following link will help you locate one.
http://www.citizensadvice.org.uk/
This link for the UK Border Agency can also help you: http://www.bia.homeoffice.gov.uk/settlement/
Also read about the new Settlement checking service
http://www.ukba.homeoffice.gov.uk/settlement/applicationtypes/applicationformset(m)/scs/
Your nearest office in London will be:
Barnet
For more information, please contact the Barnet settlement checking service by phone, fax or post.
Phone: 020 8359 6412 or 020 8359 6413
Fax: 020 8952 7352
Address: Citizenship Office, London Borough of Barnet, Hendon Town Hall, The Burroughs, Hendon, London NW4 4BG
Best regards
Anali09