The solution I will describe will work only on apache server where mod rewrite is enabled.
As first step you need to add this line to your .htaccess file
Code:
AddType application/x-httpd-php .html
this will make your frontpage executed as a php script. Now go for an rss parser script. You may want to use rss2html since it is very easy to implement, but carp or magpierss will do the job as well. You need to add the URL of the rss to the configuration file of the parser and call the file as any other php file, using the php include function.
PHP Code:
<?php include('rss-parser.php'); ?>