Not sure what you mean by screen scraping in the context of DosBox since the term has many different meanings depending on usage. Do you mean screen capturing? If so then if you read the README then you may find something....

I mean getting hold of the underlying character buffer, not the visible pixels.

uhm you can use the debugger (look for it in development forum)

and do a memory dump of a certain area (for example the videomemory)

Thanks QBix, you'll be hearing a lot more from me if I go ahead with it : )

Regards