Roots can be other colours if stained by the medium. Ones inside the medium can sometimes be pale yellow if no light has got to them, they need light to be green. I've had them turn brown from staining of the medium, if they are firm then they are good, but mushy brown is bad.
Katsols it looks like the root with the jagged edge has been munched by something
The other looks fine, the different colour on the tip is normal as they grow.