OK, thanks for the how you installed the package (HelixPlayer). Sounds like the path for realplay is in your pathing, so far so good. Installing mplayer should not change or add a plugin to the browser. You may have installed the mplayerplug-in package which does make changes to the browser plugins which does affect the browser and playing realplayer files from the browser, but should not remove any icons in KDE or Gnome.
As far as printing goes, maybe another update associated with the openoffice yum update did affect your printing. Maybe you need to re-configure your printer, for this use; http://localhost:631
instead of using the supplied system-config-printer tool.