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Default RE: bread crumb trail
Look in catalog/includes/application_top.php around line 618

find:
// include the breadcrumb class and start the breadcrumb trail
require(DIR_WS_CLASSES . 'breadcrumb.php');
$breadcrumb = new breadcrumb;

$breadcrumb->add(HEADER_TITLE_TOP, HTTP_SERVER);
$breadcrumb->add(HEADER_TITLE_CATALOG, tep_href_link(FILENAME_DEFAULT));


Take out the line (or comment out) -- $breadcrumb->add(HEADER_TITLE_TOP, HTTP_SERVER); -- to remove the "top" link.

To Change -- HEADER_TITLE_CATALOG -- to "Home"
open catalog/includes/languages/english.php

Find the line-- define('HEADER_TITLE_CATALOG', 'catalog'); --
Change 'catalog' to 'Home' or whatever you want.

Hope this helps