I just have to jump in here and tell you that some whole wheat pastas are better than others. Some brands are just horrible and are like eating dirty tasting rubber bands. Other brands are quite nice and your family might not notice the change at all, especially if served in a sauce that would hide the darker color.
A really good way to make the switch is to start off with a wheat blend pasta. There are a lot of these now and you can get them on sale. These have a nice mild taste and more normal texture. You can then experiment with finding a whole wheat brand that will be acceptable to everyone in the family. Whole wheat pasta (or even a blend) is a much better fuel for the body, it gives a little more fiber and it will keep everyone fuller longer.