I don't think you realize quite how much work is involved, and how many (conflicting) standards are going to be involved here...but probably the best route is to start with an open source browser and see how they do it. There are a few, and a quick google will find you a fair amount of info, but have a look at The Chromium Project
] - it's the OS browser behind Google Chrome.
Bear in mind that if you need detailed help with an OS project like this, you are probably going to have to talk to people who have worked on it, which means the site you get the source from, not here! :laugh: There are not going to be many people who have worked on their own browser...