Clearing the RECENT FILES list does not actually delete any songs/files.
In fact you can click on the SONGS tab, and find your songs there – or find them in your file system.
If you want to actually DELETE the songs – head in to your file system and delete them there.
This will delete all the files associated with your song!
Be sure you backup any audio files that you want to keep, and make sure you check the MIXDOWN folder and backup your song – if you want to keep it.
(The Mixdown folder is the default location where your song is saved when you bounce it out)
If you don’t know where your song is saved, RIGHT-CLICK a song name in the RECENT FILES or SONGS tab, and open the location.