Add code to themes hooks plugin or index.php to remove posts from one or more categories from displaying on the home page

Remove Specific Category Posts.php

//Code for one category
<?php if ( is_home() ) { query_posts( 'cat=-1' ); } ?>
//Code for multiple categories
<?php if ( is_home() ) { query_posts( 'cat=-1,-2,-3' ); } ?>
/**
* @author Brad Dalton - WP Sites
* @example http://wp.me/p1lTu0-9OJ
*/

// Change conditional tag to remove posts from displaying on blog or other pages
// Change category i.d's to your own