Is there a way to render without taking shadows and lighting in to account? If you just want a quick render to check placement and scale, and the whole scene is illuminated?
Shadows can be turned off in lamp settings, or in desired materials. But the best way is to go in Render option and look an the button to the right of the Render one. There is one Shadows, turn it off.
Without any light, you want see nothing, only the contour on the background. Sure, you can use emitting materials, but that is the same, unless you set different material for every object. Why the camera view in 3d view isn’t enough for this, but rendering is needed?
Another solution perhaps, is the render preview (Shift P); open it and drag it out to fill the camera view. Yet another is to change the viewport to shaded view (Shift Z) and view the scene through camera view.
For placement, can’t you just use the OpenGL preview? That’s the fastest render you can get.
If not, another option is to render the scene with normals and use nodes to “light” it.
Blend sample: http://www.clipsandscripts.com/wip/examples/no_lights.blend
There’s a little icon on the 3D window header that allows you to render a screen shot of whatever is in the window (can’t remember what it looks like - Blender’s not in front of me now, but I think it’s on the far right of the header). If you CTRL click it you will get an opengl animation rather than a still.