Website Design

i have a website but i want to enhance it. so i will be using almost the same interface but i need: - an admin page to manage all kind of content of the website.. - for different users i need different access types. i.e. an Administrator can change everything but editors can only manage their content in their language of the content for their country. - for countries they will have 2 types of content... 1st one corporate content which exists in english and marked as mendatory.. this type of content "must" be translated from english to content editor's language. screen should be splitted vertically. original english version at the top and below there should be a editor to type in local language.. 2nd one custom content available in any country.. this contents might be an article, a news, a video ... etc.. - an internal chat system should be available among users on admin side. - on admin side a file repository should be available. admins or editors should be able to send documents to other admins or editors. - website will be available for different countries. Whenever needed admin can add a new country. each country will have 1 language defined... visitors will be able to switch from one country to another or one language to another.. also users should be redirected to matching country page or language based on their ip block and their browser language. Services Management System Product Certification Training Serveillance Services and their child objects should be fully customizable. a tree-like structure preferred. whenever we sort the top nodes.. top 5 should appear on main page.. if it is more than 5 categories there might be a more.. link below them.. if they are only 5 items no need to show "more..." link... -in contact page headquarter address and selected country address for each country should be at the top and other countries below. so one of the addresses will be marked as hq and there will be at least one address for each country. when the country selected related addresses should be moved to the top of the other addresses. -site should allow us to provide search engine friendly pages. - this is the first part of the website.. if the first part is approved we have 2nd and 3rd project related to same website.. so i am looking for serious developers who will be responding on time and will be in touch whenever needed... Programming language might be .net or php.. in both cases source code required for documentation purposes.