I am trying to connect a dvd player that has red, white, and yellow connectors to a plasma TV that has red, white, blue, green connectors. I connected the dvd to the red, white and green connectors, but the color is not right, what do I need to do to get the best video colors right now I have mostly red and green colors and the other colors are distorted

Red, white and yellow is Composite.
Red, blue, green, and red and white for audio is component. You can't mix.
Use either Both Composite, both component or both HDMI, or whatever both have.

Your TV should have a set of yellow white and red. The best picture would be HDMI (if you have an upconvert DVD Player). Otherwise, the next one is as Strat mentioned, Component. Which is the red, green, and blue you see for video.

If you list models of each device, we can tell you for sure which is the best way to connect it.