495047 Complete Code Cleaning and New DB and New Features

We need to repair the bad code of full site redo DB fully speed up ( below 5 secs) site and make ready for live launch. We have spent a lot of time on the current site (via pm) and seriously don't have the mental strength to go thru a ground up whole development cycle again is there a way to finish this quickest ( by end June) using only the following elements of current site also but using templates/modules/plugins etc do et me know - All pages code correction (w3 ready)( many pages close to 300 have each 300 plus errors etc) - DB completely build new , normalise etc so that site loads sub 3 seconds ( right now with nginx its very slow we dont want to use nginx or anything site should load below 3 Bad code and DB has resulted in this - Cross Browser compatibility ( IE, Fireox, Chrome) - All current features remove some ) will be discussed. - FB login. - We have affiliate feeds pulling in products also we have features to allow vendors to upload their products and display on our site we need to also now allow them to sell the same so shopping cart. - completely bug test Site url etc by pm and completion by end June