Ubuntu will place icons for other partitions on your desktop. Do you like a clean desktop, or just don’t always need access those other partitions? Changing a value in the GNOME Configuration Editor will stop partitions from being displayed on your desktop.
Press Alt-F2 to bring up the Run Application dialog. Type gconf-editor and click Run.
In the left pane of the window, browse to apps->nautilus->desktop. Uncheck the volumes_visible option and the partitions on your desktop will disappear.
Want to keep shortcuts to some partitions but not others? Follow the other directions, and then and can create your own launchers for the partitions you want.
Right click on the desktop and click Create Launcher. In the Type drop down box, select location. Then you can give the launcher a name and the location you want to link to. You can find the hard drive icon in usr/share/icons/gnome/scalable/devices/ if you want to use it. The resulting launcher will act just like the ones that you removed in this post.