Just click on the icon you want to remove & delete it. The icons are created with the script /usr/bin/mkdesktophdicons; if you want to disable this script, just add 'exit 0' as the first operational line of line of the script. Removing the script altogether may cause problems because the calling program will go looking for a script it can't find.

Code:
#!/bin/bash
#mkdesktophdicons modified by CrashedAgain to do nothing

exit 0