Download to desktop

I’m constructing an enhanced CD menu in Flash. I’m going to be including some desktop backgrounds that I would like people to be able to click on and then save the file from the CD to a location of their choice.

Is there a way to do this - access the files system as you would when you choose a file to upload but instead are choosing a location to save that file too? And then copy the file from a Cd location to this chosen loaction.

Or alternatively is there a way to just open a pop up file window in a certain location.