Thanks for the clarifications, Kshitiz, makes it much clearer. One more thing I would like to clarify is how did Dumbledore manage to "beat" Grindelwald in that epic duel, if Grindelwald possessed the Elder Wand. Was the legend that the owner of the Elder Wald could not be defeated in a duel just a myth?
It isnt a myth - the power of the wizard matters also. Its the wizards skill also that matters. You cant expect a 1'st year hogwarts with the elder wand to beat voldemort lol. Take it this way.
Wizards power + elder wands EXTRA ORDINARY POWEr = the wizards total power.
But imagine in a case where the rivalling wizards normal power is more than the sum total, then what will happen ? obviously the master of the wand will be defeated.
Dumbledore had sheer skill. Moreover, the courage factor comes now. Dumbledore did not fear death, but grindelwald did initially. all dark wizards do. This courage must have aused dumbledore to overpower grindelwald, combined with his sheer skill and power. The wand was unbeatable, not the wizard
Also regarding the horcrux things, what happened was, that when voldemort came to kill harry whjen harry was a baby, he already had made all the 6 horcruxes, which you all know.
When he came to harry, and used the killing curse, he accidentally made him an horcrux, that is, he split his remaining little soul in his body into another two pieces, and one piece got attached to harry. Now his soul was so unstable that he NEITHER LIVED NOR WAS DEAD. his life was a misery. Do you remember, he could rely in professor quirrel in the first book ? because his soul was very weak. HE NEVER DIED THAT NIGHT, HIS BODY WAS JUST UNABLE TO LIVE.
Then, he used the diary horcrux, trying to come back, but he couldnt. NOw what he did was that all of you saw in the 4'th book - used his remaining soul and took harry's blood etc. to come back to life. Then it all started. Hope everything's clearer now.
PS . If you read the 7'th book, there's a part when harry is in voldemorts mind and recalls how his parents got killed, the exact scene. That says that as soon as voldemort fired the killing curse, something happened, and and, lol i forgot, but it says he isnt dead.