Even if it is the front page is located at the default
mysite.com/node, there are dozen's of way of populating it in Drupal with stuff that aren't nodes.
Have you looked if blocks are used to populate the front page? To check, navigate to Home » Administration » Structure » Blocks, and examine the configuration of the blocks that are enabled. The RSS feed, for instance, is probably a block. You can edit the content of blocks, or moving them to region
- None - to disable.
One problem here is that we don't know whether you predecessor has done this the right way or his own way. For all we know, he may have hacked the core or theme template directly. Things also depends on version and theme. You haven't told us what version of Drupal you're running or what theme the site uses. To answer this question with more accuracy than this general answer, all this must be known by the person writing the answer.
Three things to try:
If you're using Drupal 6, navigate to Home › Administer › Site configuration › Site information. See if there is any contents on that page that account for material on the front page. If so, you may now edit it.
Change the site's theme. In particular, get rid of any sub-themes and revert to the default theme for the Drupal version you're running (depends on version). If you're already running the default, install the admin theme as default (depends on version). If the content on the front page disappear, it's in the theme templates. Update your question with this information, and ask how to fix it. I (and others) will then update our answers.
Back up your configuration (Important!) Upgrade Drupal to the newest major version of the branch you're at (depends on version). If it is already the latest major version, upgrade anyway. If the content on the front page disappear, your predecessor has hacked the core. Restore from backup, and hire a consultant.