I just bought my first Mac (iMac) and am a complete noob to OS X. I installed couple of applications -- skype and firefox -- and now i've these 2 icons on the right side of my desktop. The icons have the logo's of the corresponding applications. I want to know if I can delete these to unclutter and how. If I click on "Finder --> Eject disk", I get the warning "The disk 'skype' is in use and could not be ejected". Did I goof up while installing these apps??