If you still have the receiver and not canceled Dish yet, I don't see a problem getting the DVR recordings off the receiver onto a DVD. I did this exact same thing. I had over 100 hours of TCM old movies recorded. I upgraded my receivers to HD receivers (2-612's,1 622). Being I owned the receiver the 100 + hours of DVR'd TCM, I did it at my pace. The 512 receiver was disconnected from the dish. I hooked it up to a DVD recorder I have. I connected the 512 to power and fired up the receiver, no input was hooked to anything. While it was trying to find a signal I hit the guide button. Once it brought up the guide I hit the the DVR button and scrolled to what I wanted recorded and started playback and hit record on the recorder. This is a real time record method, if the movie was 2 hours you need to stop the recorder after the movie is over.
Again.there was no input from dish to get a signal, just went to DVR playback and started recording. Now if you stopped Dish service they want the receiver back real quick and if you don't send it back in their time frame they will charge you for the receiver.