You are asking a pretty complicated question. First and foremost, ditch the windows servers. Open source is where it is at, 100%, especially for web.
You keep asking these questions but I am going to give you the same answer as before. Your best bet is paying for it to be hosted. It goes down, they fix it, they back up your site, and you don't have to worry about it. It can be as cheap as $5 per a month. Heck, $20 per a month gets you your own full blown virtual sever of whatever you want. That means you control the whole server...
Anyway, what you would have to do is set up two or more Linux boxes. Don't even fuss with AMP, because when you install the alphabet soup of web tools you are going to have configuration issues. Just load Apache, MySQL and PHP manually, however, most of these things come standard on Linux distributions anyway.
Depending on how you set it up and your distro, depends on where the files are stored. In many distros apache config will be in /etc/httpd. However, I have seen some things that will put apache config in /var/www, so go figure
Now once you have everything set up you will have to enable what is called a cron job, and that cron job should probably run at the very least once a day, if not maybe twice a day. The cron job will run a script which carries a set of commands like rsync and what not, and that rsync will remotely synchronize your data amongst the servers.
For it to promote itself if one goes down you will have to cluster them, which is something I am not going to even begin to try to walk you through.
So really, either you learn sever administration on top of web development or you fork over the few bucks each month to have it done for you. Plus, do you even have the bandwidth to allow multiple users to browse your site?
