File link-https://www.blendswap.com/blends/view/5387 For some reason my render have these black and white checks. Please help me to remove them. Thanks
It seems to be caused by the "use mist" in each material. I don't know why it works like that but disabling the "use mist" makes the objects solid.
Also that file isn't exactly great with scene and model work. You'd probably be better off creating your own sets. Forget about Blender Internal as the next big release won't even have it. Go with Cycles.
It appears that you are rendering with transparent background. Essentially the opposite of this question :)
To change this in your scene, (Blender Internal) go to the properties panel and change Shading alpha to sky rather than transparent.