to have a target, its not include... this is how most people use includes :
They create 2 php pages : header.php and footer.php where they put there header and footer (basicly all informations before the main content (text) and information that goes after the main content.
than in a separate file such as index.php or home.php or any other pages they do :
CODE
<?php include("header.php"); ?>
This is some content that will be at some place on my site
<?php include("footer.php"); ?>
what it does is that instead of having a code in each page like : <html> <body> your metas... and your table... you have it in ONE file which might be header.php and than your basic file like index.php where you tell him to show this code by an include. and than at the end you close all your codes with the footer.php
to have this link system :
in your index.php (must be PHP)
put this code where you want your CONTENT or MAIN TEXT (or where you replace your iframe)
CODE
<?php
if(!isset($_GET['id'])) {
include "home.php";
}elseif(!file_exists($_GET['id'].".php")) {
include "error.php";
}else{ //if all goes well
include $_GET['id'].".php";
};?>
lets explain :
the GET['id'] or the "id" is this : index.php?id=somepages its the "id" after the ?. you can replace that by what ever you want, but your urls must have it aswell.
Example : instead of
CODE
if(!isset($_GET['id'])) {
i put
CODE
if(!isset($_GET['page'])) {
my links will now be called : index.php?page=somepageshere
Than :
CODE
include "home.php";
is the First page your site will open, its basiclu the <b>src="home.html"</b> on your iframe.
Than :
CODE
include "error.php";
This is the page it'll go if you have no other pages... or if the page is not found.
And thats it :
now you need to have blank pages, or pages with some text that are in a php format and put it on the link, what itll do is in place of the code itll put your content. Just like an iframe.
Take it exactly like an iframe but without the sizing problem you use to have when you had bigger or smaller pages...
Easy to use, but kind of hard at first... but really.... once you got it... youll laugh and be happy to use this php iframe system and have your pages look like index.php?id=somepages ... coz it looks nicer

Good Luck