Depends on the connections. Some DVD/VCR combis only have the one scart socket at rear and you have a select button to choose whether DVD or VCR signal uses this to send pics to TV. This is with just the DVD player/VCR combis. With the more expensive DVD recorder/VCR combis you will probably find that they allow dubbing either way. That's DVD to VCR or VHS transfer from the VCR to DVDR.
You could, of course, use just an ordinary DVD player which plays your DVDR home movies to connect direct to the VCR input (instead of the TV) and monitor on the TV using the VCR output to TV connection.