"Hmmm, so a 2, an atheist who has no belief, is actually an agnostic? No my friend, they just don't have a belief, which makes them an anti-believer "
OK, your 3, An "anti-believer" - one who does not accept the validity of unproven beliefs - is the definition of an agnostic. An agnostic dismisses the belief in God and the belief that there is no God, because he is "anti-belief" and will not accept, either way, that which cannot be proven. He has no dealings with "beliefs".
Atheist
1570s, from Fr. athéiste (16c.), from Gk. atheos "to deny the gods, godless," from a- "without" + theos "a god" - http://dictionary.reference.com/etymology/atheist
An atheist does have belief. If he had no belief he'd be agnostic. Theist and Atheist are opposite beliefs, two sides of the same coin, two ends of the same stick. Same process, different conclusion. A-theism is defined by theism, that which it stands in polar opposition to and is a re-action to. That is why "theism" takes up most of the word "atheism" LOL. Think about the basic meaning of the words.
Theism - Advocating existence of God/s
A-theism - Denying existence of God/s
A-gnosticism - Not knowing either way.