Do i need to play EOTN to unlock the Hall of Monuments

i have searched the forums and cant seem to find this question i have brought the trilogy and EOTN and was wondering do i need to play EOTN to unlock the hall or can i just start playing Prophecies and still unlock points??

You'll unlock points without even owning EOTN, but you cannot access your hall without going to the outpost EOTN. You can check the calculator out to see what you've done at this point, point wise.
http://hom.guildwars2.com/en/

Small correction on Mollie's post. The points won't show up on the calculator page unless you add the titles to the hall first. However, you don't need to add things to the hall right away. Play as you like, and you can just add the points in the hall when you feel like going there.

so i can play through the other 3 then play EOTN and access the hall and earn all the points i have without going through the other 3 again?

Yes, you earn the stuff all over the GW world. HoM is only place to display them. But you must equip your HoM with tapestries. You can buy them from other players or get regulary by completing EotN.

Some points can only be obtained by playing EOTN, such as the destroyer weapons and hero statues. You can buy the tapestries from other users, but why do that when you can get them for free? (With seven hero teams, Mercenary heros, consumables, and the fact that almost every mission in the main story and area has rez shrines, it's extremely easy to cruise through.)