Does the back of your 722 look like this:
If so, you might be able to connect a DVD recorder via the S-Video to record the video output, and the audio via the red/black phono plugs nearby. However the video output signal may be copy-protected so you should find out from Dish whether this is the case. Remember also that only standard definition content can be recorded in this way.
I think the USB port is for attaching an extra hard disk, but needs activating for a fee from Dish. You could record to that external disk, but whether software exists to get it back off, is another matter.
There is the PocketDish media player, which I think enables you to transfer recordings from the main unit to the player for viewing elsewhere.