Urgent: Dynamic -> Static .htaccess Modrewrite

My site www.animeomnitude
Uses the current structure of

site.com/?page=page
site.com/?page=folder/page
site.com/?page=folder/folder/page

using this include code

        <?php
if(!isset($_GET['page'])) {
include "news.php";  
}elseif(!file_exists($_GET['page'].".php")) { // this also takes you to the home page if the page you're looking for using the ?page= dosn't exist
include "news.php";  
}else{ //if all goes well
include $_GET['page'].".php"; // include the page e.g if it was ?page=tutorials include tutorials.php
}  

?

PHP:

I tried using this .htaccess code

RewriteEngine On
RewriteRule ^/$ /?page=home [L]

Code (markup):

Some reason it doesn't work. It it because I have different paths for different links? e.g /page /folder/page etc?

Can someone make me a modrewrite that will work on all of my urls and will I have to change all my hyperlinks or will I keep using

< a href="?page=xxxxxx

HTML:

to do my links?

Thanks