figure border and mapping window to data coordinates

I have been using matplotlib with TkInter (TkAgg backend) and it's really nice once I got the hang of it... I have two questions though, which I couldn't find in the manual.

1. The figure window has a pretty large border around it, that seems to expand as I enlarge the window. Is there a way to set this to, say, N pixels?

2. I have some x, y window coordinates I got via Tk event bindings. How can I translate these into data coordinates?