As a non-religeous person, I've probably studied the Bible and associated scribblings more than most. I'm reading the Dead Sea Scrolls at present.
I've got several Bibles, commentaries and some scholarly volumes about various aspects of it on my shelves and in my e-readers. But I find that as I get older, I have less and less interest in studying the Bible. It seems like a waste of time to me, in my own personal life at least. (I don't mean to imply any criticism of your interest in the book.)
We know Jesus lived, there is no doubt of that, the records left by the Romans are unambiguous.
I assume that he existed, but I don't think that I can say that with absolute certainty. The Romans didn't leave any actual records of Jesus. (There's a supposed letter by Pontius Pilate, but it's generally believed to be a medieval forgery.) What the Romans did leave behind were various remarks about the early Christians. So we know that there were people preaching some kind of Christian gospel a few decades after Jesus' death. The Romans don't seem to have typically questioned the historical Jesus' existence though. The later Jews don't seem to have questioned his existence either, though they obviously questioned his religious significance. That's basically how I look at it.
So as an athiest, what can I take from the Bible? The answer is a surprising amount. Good sense, moral guidence and social etiquette. The importance of various institutions from the courts to marriage to foreign policy.
Some of the moral lessons in the Hebrew Bible aren't ones that I would favor people listening to today. Exterminating enemies in war (killing captured populations, men, women and children, even their animals), killing daughters that have premarital sex, killing blasphemers, killing Jews who leave Judaism and any outsiders that might try to convert Jews to a different religion, and on and on.
In fact, a great deal of the tension between the Western world and Islam right now is due to traditional legalist Islam's still adhering to the kind of crude morality that Christians and Jews still pay lip service to (it's the "good book" after all), but try not to ever read, think about or follow.
But yeah, I think that some of Jesus' sermons are very good. Occasionally they're extraordinary. That leaves me with the problem of picking the good stuff out from all of the nasty bits. And that applies to Jesus personally. He lived and breathed ancient apocalyptic Jewish culture. He was all about the last days and the coming of the "kingdom". So I question how cleanly we can separate and sanitize the sagely loving Jesus from all the weird stuff. I suspect that I'd be totally repelled by the guy if I ever met him as he actually was, in real life.
I think to dismiss it out of hand without even reading it properly is a mistake - A closed mind is never conducive to the learning process, and the name "Jesus" means "Teacher", not messiah or King or son of God.
That's probably true. The Bible obviously has tremendous interest from the perspective of the history of religious ideas.
But I've reached a point in my life where I find it necessary to apply a bit of intellectual and spiritual triage, I guess. I'll never have the time or opportunity to read, think about and practice everything. In my case, the Bible might be something best left for another lifetime.