.htaccess redirects to a template selection php file

How would I configure my .htaccess file if I want all requests to always load a core template selection file. I believe this could be good for a few reasons the first of which being security. Only if my php template selection code flags a file as safe for display will it display. Also, it allows me to build some interesting cms functionality like requiring a php metadata array in order to load the template file. How could I accomplish this?

Also, do you think it is practical to choose this method over others?

<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /
RewriteRule ^(.*)$ /index.php
</IfModule>

Make sure that inside the httpd.conf this line isn't commented:

LoadModule rewrite_module modules/mod_rewrite.so

(It should be **without** the '#' at the beginning)
And this is my directory tag (I'm using wamp but it should be the same, and of course restart the apache server if you changed something there)

<Directory />
Options FollowSymLinks
AllowOverride All
Order deny,allow
Allow from all
</Directory>

You can use this rule in your root .htaccess to make `core/template.php` your front controller:

RewriteEngine on
RewriteBase /

RewriteRule ^core/template\.php$ - [L,NC]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . core/template.php [L]

---
**EDIT:** If you want even real files to be routed to same controller use last rule as:

RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule !\.(jpe?g|ico|gif|bmp|png|tiff|css|js)$ core/template.php [L,NC]