make sure you type it just as the file name is... if you put a space before it you have to put the space before it to remove it also so
rmdir /var/root/Library/Ringtones/iPhone Ring.mp3
is not the same as
rmdir /var/root/Library/Ringtones/ iPhone Ring.mp3
rmdir /var/root/Library/Ringtones/iPhone ring.mp3
it must be exact... best way to check the file name is to do
then just type ls
this will list the files and just make sure the file name is exactly the same as whats there...
i think that that ringtone is built into the firmware somehow because its odd that it shows up at the top of the list... and it is the "iPhone ringtone" so it may be locked some how... it is always set for the default for sounds also...