You plug one end of a device into your VCR via the RCA inputs and the other end into your computer via a USB cable. Stick a VHS tape into the VCR, make sure it's rewound, start the capture process ...

The RCA and GoVideo decks require DVD+R (and their ... are nearly indistinguishable from the original VHS tape. Remember, of course, that VHS quality isn't so great to begin with.