from : wordpress.org/codex

When you install WordPress, you can install it into its own folder and retain the index.php that comes with WordPress. The link to enter your WordPress driven version of your site would be to this /wordpress/index.php from the root /index.php.

Helping WordPress Find Your Static Front Page

1. Create your splash page
2. Create a new folder on your site server for ????? WordPress? the new static splash page?
3. Download index.php WordPress file and open it in a text editor.
4. Change the require(’./wp-blog-header.php’); line to require(’../wp-blog-header.php’);
5. Save and upload the modified index.php file into the new folder.
6. Login into your WordPress Administration Panel, and go to Options→General.
7. Change your Blog URI pointing to the new folder. For example, if your site is http://example.com, and the new folder is called blog, enter http://example.com/blog.

Now you can upload your splash page to your root server folder.

Change Apache Configuration File

There is another form to upload your static front page without moving all your WordPress files to another folder.

When you request a folder in a Apache web server (for example the folder called /chouette), the core of Apache will search for a file with any of the names in a list saved in httpd.conf. If your server lets you use .htaccess files for change the original configuration, you can follow these steps:

1. Open the .htaccess file from your root web folder in a text editor.
2. At the top of the file, add:

DirectoryIndex home.php index.php

Save and upload the modified .htaccess file.

You need to mention index.php as a second choice, otherwise you will not be able to access the index.php in directories below the wordpress root directory unless you explicitly mention it in the URL. For instance, the url:

http:///wp-admin/would not work.