Loading and unloading levels

Hi guys

I am in the process of using a level file as a menu system, mostly as there doesnt seem to be a gui editor for xna, The issue i'm having is that if i have a level loaded, and i load the next level, the old data is not cleared, i unload the last scene and load the next one I just get a black screen, is there something Specific I should be doing?

Many thanks