Which text/source does eNotes use for its original version of Shakespeare Hamlet?
As there are several "original" versions of Hamlet (1603, 1610 and 1623), as well as thousands of later versions of the text, I am interested in establishing which one has been used for the eNotes version.
I did not edit the Entoes text of Hamlet, let me be clear about that upfront, but I have read enough different editions (and it's better to call each distinct Hamlet a different "edition" rather than a different "version") to have a general understanding of why there are different editions of this (or any) Shakespeare play.
This e-text that is available on the Entoes website is also reproduced in paperback as a Prestwick House Touchstone Literary Classic. This is the real "author" of this edition, in that the editors working for Prestwick House would have the job of looking through the Quartos (there were five) and the First Folio to cull together the different components that fit into what they consider to be the "correct" edition of the play. The Quartos and Folio do correspond to some of the dates that you suggest, and it is these different versions of the text that are mixed and matched to create any edition of the play made available today.
So, whether you pick up this Prestwick House edition, or the Arden, or the Folger, you are reading a text of the play patched together by an editor (or group of editors) who have chosen the pieces that they prefer from all the Quartos and Folio to create their edition of the play.