The reason it was sent to superior court is because eitehr the counterclaim exceeded the amount allowed in Mag Ct or the claim was outside what the Mag court could do. I do suggest that you answer the counterclaim and asset whatever affirmative defenses you need to assert. I do not suggest letting a pleading go unresponded to, especially under GA law which differs from other jurisdictions
You don't need to file a counterclaim if you filed a claim in the first place. As for the answer, you can either hire a lawyer, or buy a good "how to" guide about your state's Magistrate courts to help you.
I'm only licensed in CA. Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.