Retrieving data from hard drive [closed]

I have a Video receiver (Sagemcom RCI88-320) for watching and recording television. The HDD of the receiver is almost full and I would like to take the movies on the receiver and put it onto a computer HDD. How would I go about doing such thing? Im not necessarily looking for a full description of what to do, even a few tips or ideas how to start would be nice as I have no idea where to start.
Thank you very much!