There is no good or bad side of the brain, and the differences in sides are largely overstated. Both sides of the brain have the ability to control the whole body, and neither side is solely (or, arguably, primarily) responsible for math or language. People can live without huge portions of their brains (well, fucntionally).
No, the right side of the brain is not better, because the logical side of the brain is the left side, and logical thinking is very important. Logic helps us do basic things. While creativity is important, being logical is a good thing, because logic helps us make good choices that keep us safe. Both sides of the brain are important, but the right is not better.