Kris,
Write down the claims and then do independent research. It is futile to discuss anything with people who have a mindset against any other information that would disprove their claims. Your investigations and information gathering is for your own decision making; it's not to convince someone else.
You should write down what you want to research.
"every ancient historian can agree that Jesus existed and that it is "Cemented in history" and that the documents and parchments are just overwhelming evidence of Christianity.."
Then look at unbiased scholarly writing or sources to see if what they have found lines up with the claim you are investigating.
This message board has plenty of evidence that disputes this claim with the sources and names of ancient historians listed. That would make it really simple to check it out. Anyone who has accurate information will give sources and you will be able to check it out. Naming ancient historians who were eyewitnesses that wrote about Jesus is not possible because none of the writings about Jesus comes form eyewitness accounts.
On this message board:
Atheist Community of Austin (topic) Scholar facts about Jesus
When you are given the names of the historians (sources, books and authors) you shouldn't have a problem checking it out. This is a discussion board and if you find something you want to discuss or ask questions about you can. I have found the information very helpful and I have found many books that were very interesting to read. I have found that the people who have answers from their own study and research with sources to be extremely intelligent. I research answers that I find in books written by scholars, since that is the only actual way to research any information from any source. That usually leads to finding out even more answers.