There are several inexpensive ways to convert VHS tapes to DVD discs, but the one that is best for you depends upon the specific equipment you have on hand. Regardless, though, as long as you have a VHS player and a computer with a recordable DVD drive, the only expense you'll have is for connecting cables and blank DVDs. Here are some options for you.
Direct to Disc
If you have a VCR player and a recordable DVD player, you can simply hook the output jacks of the VCR into the input jacks of the DVD. Put a blank disc into the DVD player, and then set the player to "record." Then press the "play" button on the VCR. You can monitor the audio on a pair of headphones plugged into the DVD's headphone jack.
Direct to Computer
If your computer system includes a recordable DVD drive, it will also have software that will enable you to take input from external devices (like video cameras and VCRs) and simultaneously burn the data on to a DVD. In this case, simply connect the output jacks of the VCR to the input jacks of the video/sound card on the back of the computer. Place a blank DVD in the drive and open your resident DVD recording software. It will have an "input" or "import" switch that will have to be set for "VCR" or "analog" input. Press the "play" button on your VCR and then click the "record" button on the DVD software.
There may be instances in which you might want copies of the video both on your computer's hard drive, and then also burned to a DVD. In that case, follow the instructions in Section 2, but save the input as a file, instead of burning it directly to disc. Once the file has been saved to your hard drive, you can then burn it to a blank DVD disc.