Some of the stories that have been thoroughly debunked & reinterpreted:
*) creation 6000 years ago
Forget it. The age of the earth, solar system and universe ineluctably points at a much grander design, to be measured in billions of years rather than puny thousands.
*) garden of Eden
Funny enough, technically there's a core of truth here (homo sapiens did have its origins in Africa to subsequently spread all over the globe in 2 or 3 major migratory waves), but apart from that it is just another feeble campfire tale.
*) Adam & Eve
Modern genetics easily disproved that one. "Mitochondrial Eve", the mother of all people alive today, really did exist; she is an unavoidable consequence of both mathematics and biology. But a) she's estimated to have lived some 150.000 years ago, and b) she was obviously not the only living woman at that time, certainly not produced by taking a rib from Adam (actual biology rather strongly refutes that one).
*) the deluge
Quite obviously, there never was a global flood, as there were several advanced civilizations around at the time and literally nobody noticed a thing. (But then, there are *so* many things wrong with this story.) Another nice fairytale, easily traced back to the epic of Gilgamesh and even earlier stories. The levant being crossed by some great rivers (Nile, Euphrates, Tigris, Jordan), an occasional disastrous flood was only to be expected (the south of the Netherlands had its own flood in 1953, which was thankfully not incorporated in a religious myth - yet?)
*) Abraham, Isaac and Israel
Thanks to archeological findings, we now know that these stories were circulating and written down during the 7th century BCE. If referring to actually existing persons at all (which is highly doubtful), these were 3 separate (and simultaneously circulating) stories with their origins in different parts of Israel and Judah. It was someone's brilliant idea to unify these stories by weaving all the heroes & sagas together in one big divinely sanctioned family tree. (Quite possibly, we've got King Josiah to blame for this: he ruled Judah in the 7th century BCE, conveniently "discovered" a divine "book of laws" while building Jerusalem's new temple, destroyed all other temples, centralized worship, outlawed concurrent religions and thus effectively established a state religion.) The Good Book goes to great lengths to establish genealogies; Adam, Noah, Abraham, Lot, Isaac, Israel, Moses, David, Solomon, all the way up to Jesus - everybody was "proven" to be direct kin under the auspices of the Judean warrior god YHWH (one of the many gods of the Canaanite pantheon and a competitor of the Israelite god El or Baal, often represented as a golden calf.)
*) Abraham leading his people on a journey to the promised land
Never happened. Archeology, anthropology, written records - not a trace.
*) Joseph (with or without his magic coat) in Egypt
Plausible, as Egypt had many immigrants hoping for a job (the country being comparatively fertile as compared to the drought-stricken regions around, so there were plenty of opportunities). After living there for 430 years, growing in numbers, acquiring property and freedom, you would expect his descendants to feel at home by then, and not still pine for some mythical "promised" land, but maybe people were different then.
*) Moses "taking his people home"
The exodus, one of the best-known (and geopolitically important) bible stories, certainly never happened, as it is simply incompatible with all geographical findings. Also, the "pharaoh" mentioned was probably Ramses II, who lived about 500 years too early. Another good argument: Moses leaving Egypt with more than half of the population (the Israelites being an actual majority in Egypt by then) would seriously disrupt Egyptian daily life and drastically change society. Egypt's meticulous bookkeeping records don't offer a single line of evidence.
*) Joshua's conquest of Israel
Never happened either, as the cities described (Jericho among the most famous) were already deserted, destroyed hundreds of years before. Once more, the numbers simply don't add up. Also, at least a 100 years after the purported conquest, there were still Egyptian strongholds all over Israel and Judah, two small kingdoms in uneasy proximity to that great empire.
*) King David, the all-important founder of Israel
One King David apparently really existed, only about 500 years *before* Abraham, which makes it a tad difficult for him to be a great-grandchild of good ole Abe. Furthermore, the city of Jerusalem (to this day called "city of David") during his time was a cute little town on a hill, very far from being the mighty city state he's credited for.
*) Solomon, David's wise son, mighty king and great builder of a sprawling empire
Hardly, what with Israel & Judah - independent and rivaling countries that were never ruled as a united "Israel" - being uncomfortably squeezed between the vastly mightier Egyptian and Assyrian empires for centuries. Furthermore, the cities attributed to him were built at various times, in a building style that was already in use for centuries (a rather unscientific but perhaps understandable tactic of "forcing the shoe to fit": similar structures were discovered in those cities, so it was automatically assumed they were built at the same time, by the same architect. Once more, reality - in the form of mason's marks and carbon dating, among others - intervened.)
*) When Necho II, pharaoh of Egypt, murdered Josiah king of Judah, he interrupted a line of divinely-blessed rulers, descendants of David called "messiah" (anointed one). Very soon afterwards, the kingdom was eradicated by the invading Babylonians. The majority of people was killed or enslaved; a minority of priests and scribes was exiled (see Psalm 137, "By the rivers of Babylon"). In the face of such adversity, it was no more than natural that stories arose about a possible future messiah who would restore the splendor of the ancient kingdom, a warrior king to establish a divine world state. In the same vein, shi'a muslims are still waiting for their hidden imam (remember that islam is just another iteration of judaism).
If historical events didn't happen as described (which they didn't), there never was a divinely-decreed exodus to (or conquest of) the "holy land" of Israel (there wasn't), a land that never actually existed as such (it didn't: Josiah's unification attempt was the first of its kind, and he was murdered before his plan could be implemented), this makes the whole Judean claim a rather shaky one. No wonder then, that biblical archeologists are hell bent on proving the scripture's veracity, and also that no digging or researching is allowed in the inner city of Jerusalem, as this would undoubtedly divulge several more skeletons from history's closet.
I think these findings show us the correct way of interpreting the bible: it is history after all - history of sorts, though. Several of these stories were "true" in that they actually happened, but most events have been heavily tampered with, an overarching narrative juxtaposed to fit a political as well as a spiritual agenda. In a sense, it would be better to call the book propaganda, an attempt to unify the exiled, subjugated and broken-spirited people of Judah to retain their identity. To that extent, great statesmen, people, countries and even gods were seriously downplayed, and their achievements unscrupulously falsified & confiscated. Seen in this light, we can safely discard all metaphorical interpretations, as the old testament in the end boils down to a ruthless socio-political pamphlet, no doubt interesting and exciting for archeologists to reconstruct, but devoid of any supernatural content.
So, to paraphrase the X Files: the truth really is out there. Anybody can go and look at archeological sites or the millions of artifacts exhibited in museums all over the world, or read any of the thousands of books and articles published on the matter. If, in the face of this overwhelming amount of evidence, you still want to pretend that it's all a true story, I'd have to accuse you of wilful stupidity. Or maybe, as I suspect, many religious people do have an inkling that not all is well with the bedrock of their faith, so they just close their eyes/minds (for whatever reasons), pretend they still believe it all and hand the same old nonsense down to their kids, perpetuating the folly. (Even worse, in my view, are "progressive" christians who don't believe in large parts of the bible and cheerfully sacrifice most of the consistency and even necessity for some "eternal" truths and moral values, carefully cherrypicked from amidst the rubble. In which case, why not simply ditch these fairytales altogether and stick with humanism, I'd say.) Because once you start designating certain parts of the mythology as fairy tales, or at the very least heavily distorted political history, instead of divine revelation, the whole edifice might come tumbling down, even without the help of a trumpet. I for one think that should be thoroughly exhilarating and liberating.
[For further details, I recommend for instance the illuminating "The Bible Unearthed" by Israel Finkelstein & Neil Asher Silberman]