As already is clear, b) isn't possible without someone writing a script for it. BTW, I was confused about talks about "pads". What you describe here is a copper zone, not a pad. A simple script could do that, but such script doesn't exist ATM.
But the case a) can be done easily at least with the latest nightly builds and the upcoming 5.0 (which we all wait for eagerly). I don't remember anymore how well 4.0.7 supports it, but the development version supports attaching net for a zone. Just draw a filled polygon shape to a copper layer - when you start, a properties dialog pops up and you can select a net amongst other properties. That works in the Board Editor - In the Footprint Editor you can draw a filled polygon and "Create Pad from Selected Shapes" if you need a reusable footprint with a polygonal pad. And it looks like you can import a DXF file in the Footprint Editor, too.