And you sir, are full of it. I am a Christian, and I believe what Jesus taught. He affirmed the old testament, and He is credited in the new testament as the "Creator of all things". An "informed christian" as you put it, should know that much, at a minimum. I don't know who you are talking about, but they are certainly not Christians in the sense that they are followers and believers of the Christ.
Yes, Christ affirmed the old testament as part of our moral and spiritual heritage. I don't remember his saying that it was a history book though. It's scripture, not history. When are you people going to wake up and realize that.
There are more than a few things in the old testament that simply could not have taken place. Take the flood for example. The bible is very specific about how the ark was built, right down to the last cubit. It's a very simple calculation and I suggest that you do it for your own satisfaction. The ark only had about 100,000 square feet of floor space. If we included only the 5,000 mammal species and 10,000 bird species that are alive today and multiply the numbers by two, we get only about 3 square feet to store each animal and feed for a year. And this doesn't even include the other species, such as reptiles that can't swim.
It's obvious that all of this could not have happened as the Bible presents it and forcing one's self to believe this as historical fact just detracts from the real, deeper spiritual message in the scriptures.