Up until 2010, DVD Recorder/VCR combos were very common, but now they getting very scarce, as are DVD recorders in general. However, they are still in demand.
All DVD Recorder/VCR combos feature VHS-to-DVD and DVD-to-VHS internal cross-dubbing capabilities for non-copyguarded DVD and VHS videos. However, if you already have a working VCR that you don't need to replace, and you buy a separate DVD recorder, all you would have to do to copy from the VCR to DVD using a DVD recorder is to hookup the VCR's AV outputs to the AV inputs of the DVD recorder (which works much like a VCR) and simply copy your video (if non-copyguarded) to DVD.
DVD Recorder/Hard Drive Combinations
There have been DVD recorders from a few manufacturers that include both a hard drive and a DVD recorder in the same unit, but as of 2007, they have become increasingly rare in the U.S., although they are very common in Asia and Europe.
A DVD recorder/Hard Drive combo is actually a very practical system, as it allows the user to copy raw footage or record a series a programs to the hard drive and then edit or copy smaller segments or the entire contents of the hard drive to a blank DVD. Also, another benefit of this type of unit is that if the DVD runs out of space during recording, the excess video is automatically recorded onto the hard disk, which, once again, can be copied onto another blank DVD at a later, more convenient time.
The hard drive feature on a DVD recorder is very useful for temporarily storing your video, either from you camcorder, TV programs, or other video sources. You can record video either directly to DVD, or the hard drive. You can even do some basic editing before putting your video on DVD. One important note: You have to remember that the DVD recorder's hard drive is for recording video and audio only; you cannot use it to interface with a computer for storing other types of files.
However, it must be re-emphasized that manufacturers, such as Sony, Pioneer, and Panasonic, appear to have stopped making DVD Recorder/Hard Drive units for the U.S. market. On the other hand, they seem to be very plentiful in Europe and Asia. For an interesting perspective on why such a practical video recording option seems to be disappearing, check out the article from CNET.
Also for more perspective on my DVD Recorders of all types are disappearing, read my artile: Why DVD Recorders are Getting Harder to Find.
Proceed to the next question: Can a DVD recorder record Dolby Digital 5.1 or DTS surround sound?