Smaug's family is never mentioned. In fact dragon origins are rather ambiguous. What is known is that dragons came into the world due to the corruption of the creator's song, by Melkor. His discordant addition brought evil into the world, dragons included. It is not explained whether dragons reproduce, or if all dragons were created at that same time, or if there is some other mechanism to explain how they appear.
Smaug only appeared in the Hobbit, where he was killed and he never appeared again (because he was dead). So smaug was not in the Lord of the Rings trilogy, but he was in the Hobbit.
The HobbitThe Fellowship of the Ring, Book IThe Fellowship of the Ring, Book IIThe Two Towers, Book IThe Two Towers, Book IIThe Return of the King, Book IThe Return of the King, Book IIThe Silmarillion is another book that Tolkien also set in Middle-earth thousands of years before the first of the Hobbit books, but it is a history of the Elves and does not concern itself with Hobbits (except briefly in its final chapter where it reviews the events of the end of the Third Age from the point of view of the Elves, which differs slightly from the point of view of the Hobbits).
Smaug doesn't recognize the scent of Hobbit, although he knows what dwarves and men smell like.
The main conflict in The Hobbit is trying to regain the Lonely Mountain from Smaug the Dragon.
Lake town
The Desolation of Smaug
Yes. The second installment will be called The Hobbit: The Desolation of Smaug.
The Hobbit; The Desolation of Smaug will be released December 2013
Yes, the Desolation of Smaug
smaug dies
Smaug the dragon was voiced by Benedict Cumberbatch.
No, he makes it back home. After all, he does have a part to play in The Lord of the Rings.