removeChild() and delete

Hi,
I have a large ProjectMenu class that is added to the display and contains many other classes. These have many events within each of them, such as rollOver, rollOut, enterFrame, mouseDown etc…
When a button is pressed for example, I want a ProjectGallery class to be created, fair enough. I also want the ProjectMenu to be removed from the display. Current, I have it so that when it is added events like stage.onResize, enterFrame are added, and when removed from display these events are removed. But also the classes within them have listeners that are not removed. The ProjectMenu class as a whole takes up quite a lot of CPU/Memory. Should I delete the instanceafter it is not being used, and re-create the instance when it is needed again, or will removeChild() be sufficient? I except the answer will be to use the delete keyword but I need some more info on what kinds of things will be using CPU/Memory.
Thanks for the help,
Dan :be:

-yeh ok i read it http://www.kirupa.com/forum/showthread.php?p=2129547#post2129547
-autoformat is killing me :frowning: taking out every bleeding parenthesis