The bottom of the B is most likely just
Machine Doubling or it could have taken a hit from another coin. True doubled dies are not shelf like in appearance and will usually be seen on more than one letter/number/etc...
The one that looks melted is just a melted coin. It will not have the copper look because it is a zinc penny with a copper plating that most likely melted away in the fire.
A forum member named "Coop" put together an excellent educational DVD that shows exactly what is and isn't considered an error. I would recommend getting a copy if you can. The pictures he keeps on file are excellent learning tools.