Today, the DVDs that you buy have macrovision protection to stop that. Since it's recently been ruled in court that it's ok to do this, I'll share how it can be done.
1. Duplicate the DVD with DVDSHRINK and along the way the macrovision will be fixed.
2. Place the new DVD into the DVD player, play it and press record on the VHS recorder.
On most hardware this will be all that's needed. If that doesn't work, then your DVD player is reintroducing macrovision and you replce the DVD player.
Is it possible to copy a DVD to a video tape and , if so, how does one do it?