Delete files?

Hello all,
Just bought a new Zune 30GB and want to take off the pre-loaded songs and videos that come on it. How do I do that? When plugged into the computer they do not show up on the list so I am not sure about how to get rid of them, they are cluttering up my Zune! thanks

i just bought a 30g zune. In order to delete the files on it i played one of the preloaded movies and while it was playing i plugged it into my computer and launched the zune software. the software then picked up all the audio and video files that came with it and i was able to delete them. hope it helps.