I imagine him to be kind of big and beefy instead of long and lanky like that.
PS. I just auditioned for the elf extras... I pray I get a call back some day
Smaug lay, with wings folded like an immeasurable bat, turned partly on one side, so that the hobbit could see his underparts and his long pale belly crusted with gems and fragments of gold from his long lying on his costly bed.
He thrust his head in vain at the little hole, and then coiling his length together, roaring like thunder underground, he sped from his deep lair through its great door...