> What I have never understood, is how can you not take the Bible literally and just kind of pick and choice what part to belive or not to believe.
The idea that Christianity is about the Bible is a relatively view of part of the Protestant community that many Christians who don't hold it view as a form of idolatry.
Christianity is, in other models of Christianity, about a personal decision to come to God through Christ; the Bible is a uniquely useful tool in this, in those views, as a collection of works about the relation of God to humanity, and particularly (in the NT) about Christ and his teachings, which, understood properly (which may not be literally for all parts; just as much of Christ's teachings are explicitly parables, much of the rest is often viewed as illuminating metaphor rather than factual history or commands) is understood, in those views, to free of moral error. In many such views (including the long-standing view of the Catholic Church) it is one of the two main sources of the faith, alongside sacred tradition.
The idea that the Bible is the sole source of Christian truth, or that it is entirely literal, are novel and minority opinions within Christianity. (The groups holding them are more relatively prominent in the US, and definitely more political prominent in the US, compared to other Christian groups than they are globally within Christianity, but even so there are quite large segments of American Christianity that don't follow these relatively newfangled approaches.)
> How is this process of picking and choiceing from the Bible and 2000 years of Christian history not the same as making up your own morality
Everyone is using their conscience to make their own decisions about morality, even literalists. That they choose to accept what someone tells them the canon is (about which there are disagreements among Christians -- and the canon favored by literalists is, like literalism itself, a recent change from the historical canon), and to accept that someone tells them the canon must be approached literally, and to accept the authority of a particular version or translation of the canon to be taken literally, and to then either choose their own or choose to take someone else's guidance on how to read the amibiguities are contradictions that arise when the text is viewed literally -- all of those are choices. Its kind of dangerous to think that the decision to delegate accept someone else's word for how to make these choices stops them from being choices.
Christianity, whether with or without literalism, doesn't evade the need to make decisions about morality.
> Seems to me, that the only thing 'being Christian' is (outside of the institution), is that you take some more of your morality from the Bible compared to all other books.
Except for those holding to a rather extreme version of the (also new) doctrine of sola scriptura, Christian's don't generally believe that books (whether one or many) are the sole source of morals.
> Why not just go all the way and look at all books and history to make up your own morality?
What stops someone from being Christian who considers all sources (not just books) in informing their conscience. Note that neither the Nicene nor Apostle's Creed -- generally held by mainstream Christians as the uniting features of Christianity -- makes more than a passing reference to Scripture (and that only in regard to the alignment between it and Christ's Passion.)
What keeps someone Christian -- or fails to, if it withers -- is their belief in God, Jesus Christ, and the Holy Trinity, not their dedication to a book.