What is the quest (or quests) which may be deemed as final in Guild Wars? I am not talking about missions. I am talking about quests after all missions. What is the must final quest?
I am not entire sure what you are asking about in your question, but here is a list of stuff that may fall under what you are interested in:
Challenge and Elite (none storyline missions/quests) - Fissure of Woe, Underworld, Sorrow's Furnace, Tomb of Primeval Kings, The Deep, Urgoz's Warren, Mallyx. These are are all elite missions/zones that grant unique greens, possibly minis, and other rewards is not related to the storyline.
The series of War in Kryta quests that were added in over the previous year or so which leads up to Guild Wars 2 are probably the latest in terms of story (and possibly the final story related missions).
The Vision of Glint quest series can be done after the prophecies missions.
The final quests for each campaign are: Hell's Precipice (prophecies), Imperial Sanctum (factions), and Abbadon's Gate.
The Eye of the North update has a direct link to events in GW2. The final mission for EotN is A Time for Heroes.
Filling up your Hall of Monuments or maxing all titles (very challenging and impossible for certain discontinued titles) may be considered the final quest for some.
Updated as of 8/18/2011