One of the cheapest ways is to use a Device that converts the VCR video signal to a video data file. A decent device runs around $50 with basic functions. So you basically need the Converter Device (which comes with application software), a VCR (to play the tape), and a PC to run the software and save the video files. You can then manipulate the video files by editing, overlaying video, transitions, etc., and finally burning it to a DVD.
There is actually more than one device that will help you turn your VHS tapes into a DVD. You can use a Combination Unit, a video camera, a computer, an external DVD burner, and a VHS to DVD conversion service. Just make sure you have your VHS tapes, blank DVD R, and a DVD burner.