Videotape to DVD conversion has some opportunity to enhance the quality from the original filming.
One myth, however, is that videotape can fade over time. The truth is that videotape is not like film. It is magnetic medium so it doesn’t fade like 8mm film can. Rather the tape can become demagnetized, and video/sound physically lost. This is different than acutal film losing color over time.
However, the quality of the video can be tweeked a bit very economically. Usually, a VHS to DVD vendor will include color enhancement in the cost of the conversion.
Two basic things can be done: brighness/contrast adjustment to make images more visible and sharper and the RGB color bands can be adjusted to reduce redness, for example.
In these two ways, your old videos can actually be a little bit better than when they were filmed!