A server is a computer that holds files and maybe programs, it could sit in the basement of an office building and the office workers that need to work on those files (had in the old days a monitor; today they have a computer) that would ask the server for a file and maybe the program needed to work on the file. Nothing was kept on the computer on the workers desk. In the age of the internet, the server can be anywhere in the world. Soon maybe they will be on satellites. We, the users, point our computer to the server by typing an address into the address bar of our browsers, like: http://www.codingforums.com
The server will send us the main page of the site we asked for. They will show on the browser with no problems for all computer operation systems. A special server for IE7 is not needed. The files you write will be placed on that server. More info here: http://en.wikipedia.org/wiki/Server_%28computing%29
You can put a small server on your computer to act like the bigger ones. I use WAMPSERVER, you can get it here: http://www.wampserver.com/en/
Simple html with form to send information to another file on the server.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<form method="post" action="my.php">
First name: <input type="text" name="firstname"><br>
Last name: <input type="text" name="lastname"><br>
Password: <input type="password" name="pwd"><br>
<input type="submit" value="Submit">
When the submit button is press all info in the text fields will be sent to the server and to the php file. You can start studying php here:http://www.w3schools.com/php/default.asp
Don't know what else to tell you. Good luck on your project.