Copying Multiple Layers in 7.0

I have Photoshop 7, and would like to copy multiple layers into another document while still retaining the ability to edit the layers independently (without flattening the image). In this case, I have a character I created with various shapes, and would like to put him in a background where I can edit the layers to create various frames of animation (i.e. move his eyes and hands). However, I want to do this with multiple characters, so putting the background behind him isn't an option.

EDIT: I just remembered that you could drag layers into other documents. I put them in a layer set and moved them.