Fonts and sounds are removed by dragging them out of the System file.
1) Quit all programs that are currently open. You'll get an error message
if you try to remove a font or sound when any programs (other than
the Finder) are open.
2) Open the System file. This may take a few moments if the file is large.
3) Select the icon of the font or sound you want to remove.
4) Drag the icon out of the System file window. To discard the font or
sound, drag it into the trash. To save it for future use, drag it
anywhere outside of the System file.