Got a little spot of rust....
#5
Use one of the rust removers available at auto stores, sand it, prime it, paint. At a minimum sand it to remove the rust before it eats away more then what it already has.
#6
Simple quick fix and will be fine. sand it till the metal is clean and use some rust preventative primer. If you want to go nuts with it get a pint of por-15 or something similar and top coat it.