You can't change a smart playlist like the recently added list (it's too smart ). But if you press alt and delete, you will remove the song from the library, if that's what you want.
nah i want it in the library but i don't want it in the playlist because it is a whole bunch of stand up acts and those are kind of dull to listen too on the road
Just edit the playlist and add "Name/Album/Artist > Is not > [type unwanted item here]" for each thing you don't want. If there's too many songs to add another condition for every item you don't want, put all your unwanted items in a regular playlist, and tell the recently added list to not include songs in that playlist.
Go 'head, be gone with you. I think this is a pretty good idea. Just add genre-based tags that will eliminate unwanted items.
The other thing to consider doing is... if you don't want those audio tracks on your iPod period, then set the ipod to only sync checked items and uncheck those tracks. Option-click or some modifier + click on the check box also unchecks all visible songs in the browser. So, if you go to the spoken word or whatever you call it category, and you option-click one of the check boxes, they'll all get unchecked and you can prevent all of them from showing up on your 'pod.