This totally worked for me in wordpress
Edited /wp-includes/default-widgets.php file and searching for rss2_url around line 290
Original code
<?php wp_register(); ?>
<li><?php wp_loginout(); ?></li>
<li><a href="<?php bloginfo('rss2_url'); ?>" title="<?php echo esc_attr(__('Syndicate this site using RSS 2.0')); ?>"><?php _e('Entries <abbr title="Really Simple Syndication">RSS</abbr>'); ?></a></li>
<li><a href="<?php bloginfo('comments_rss2_url'); ?>" title="<?php echo esc_attr(__('The latest comments to all posts in RSS')); ?>"><?php _e('Comments <abbr title="Really Simple Syndication">RSS</abbr>'); ?></a></li>
<li><a href="http://wordpress.org/" title="<?php echo esc_attr(__('Powered by WordPress, state-of-the-art semantic personal publishing platform.')); ?>">WordPress.org</a></li>
<?php wp_meta(); ?>
Edited version commented-out unwanted code
<?php wp_register(); ?>
<li><?php wp_loginout(); ?></li>
<!-- Comment Zone
<li><a href="<?php bloginfo('rss2_url'); ?>" title="<?php echo esc_attr(__('Syndicate this site using RSS 2.0')); ?>"><?php _e('Entries <abbr title="Really Simple Syndication">RSS</abbr>'); ?></a></li>
<li><a href="<?php bloginfo('comments_rss2_url'); ?>" title="<?php echo esc_attr(__('The latest comments to all posts in RSS')); ?>"><?php _e('Comments <abbr title="Really Simple Syndication">RSS</abbr>'); ?></a></li>
<li><a href="http://wordpress.org/" title="<?php echo esc_attr(__('Powered by WordPress, state-of-the-art semantic personal publishing platform.')); ?>">WordPress.org</a></li>
End Comment Zone -->
<?php wp_meta(); ?>
