The Ancient Greeks were the Mycenaeans, they built the great citidels at Pylos, Mycenae, Tyrins and others.
They were the Acheans, they had a warrior culture, war, piracy and pilage were their main hobbies. They were also apparently traders and their is evidence of art being influenced by the Egyptians.
Palaces were built around a central "feasting hall", they were usually stone on the first floor and wood above, they had a large number of storerooms and records from Linear B tablets show that these places were administrave power centres controlling relatively large terretories compared with the later City States.
There is evidence that the econemy was essentially feudal and that writing may have been the preserve of a specific cast. All Linear B tablets found so far have been administative in nature.
The Kings, I believe the word translates as war leader, of these people were usually six and a half feet tall and were burried with armour, swords and other grave goods. Women were usually buried with items such as needles, combs. The usual kind of grave goods for a wealthy prehistoric society.
In War soldiers carried twelve foot spears and bronze swords usually with a blade about 28 inches long, although both longer and shorter varrients have been found from different periods.
The Warrior wore almost full plate armour, including breast, back, skirt and shoulder plates, as well as greaves and a helmet made of layered pieces of boar tusk. Later shirts of bronze scales appear to have been worn.
The Mycenaean period covers the years 2500-1200BC. The Fall of the city on the Hisaralisk reconded to be Troy conincideds with the end of this period.
The Trojan war is generally recokend to have been a historical event, however how much the Illiad truly represents this event is anyone's guess. Homer does agree with much of what has been uncovered about Ancient Greece, it should be noted that he was singing 400-600 years after the event.
What destroyed the Mycenaeans is a question of accademic debate, there is certainly evidence that there might have been invaders, probably from modern day Yucoslavia.
What is known is that the fires which consumed ancient Greece were hot enough to fuse together the stones of the city walls. What has been suggested is that the ten years of fighting at Troy so sapped the Mycenaean warriors that martial skills declined and they were unable to repel their attackers. Mycenaean Greece is the only example of a culture which actually lost the ability to read and write.
Around 1000BC the Dorians arrived in Greece, they apparently defeated those of the Acheans who remained, since most had fled to their colonies on the Mediteranian. The Dorians are the main ancestors of the Classical Greeks.
FYI: Classical Greece is the period after the Dark Ages, Ancient Greece is before.
FYI 2: Obviously none of the above is known for sure, and I don't have my notes with me.