New Player Lore Questions

[Hainiryun]

Don't feel bad about asking questions, there's a lot of lore to take in and a lot of what you're asking about is actually tied to the original no longer extant version of the game which acts as backstory for the current version.

So to address each of your questions in order

1/2) the Old Guy is the Archon Louisoix Leveilleur, a notable sage from Sharlayan, the largely non interventionist island state to the west of Eorzea. He and 12 of his students formed the Circle of Knowing, a group vaguely dedicated to the "salvation of Eorzea" and he and several members of the Circle traveled to Eorzea in 1562 (17 years before the current day), a move which drastically contradicted Sharlayan's non interventionist stance. He worked to combat the threat of Primal summoning and also attempted to unite the three city states to reform the Eorzean Alliance to combat the threat of a renewed Garlean invasion, which had stalled after the destruction of the flagship Agrias at the battle of Silvertear Skies a year prior. This eventually led to him becoming a tactician for the alliance forces at the Battle of Carteneu in 1572 (which is depicted in the cinematic).

He also set plans in motion to prevent the cataclysmic fall of the lesser moon Dalamud onto Eozrea, which was a product of the Garlean "Project Meteor" supposedly intended to destroy Eorzea as an easier alternative to conquering it and a means to "cleanse" the beast tribes and their primals from the realm by dropping a big ol' rock on it. By the point of the battle adventurers (the 1.x players) had already fought and slain the instigator of Project Meteor, Nael Van Darnus but had failed to stop the moon's descent. With no way of stopping it from falling Louisoix devised a plan to summon incarnations of the Twelve (gods worshiped by the people of Eorzea) at Carteneu to protect the realm from the worst effects of moon's impact.

Which brings us to your second question, the Dragon in the cinematic is the Elder Primal Bahamut. Bahamut was sealed in the aritifical moon Dalamud thousands of years prior by the Allagan empire, which Nael had been aware of at the time, being tempered by Bahamut through the Lunar Transmitter and instigating the project in order to free the dreadwyrm. When the moon entered the atmosphere it began to break up and Bahamut was freed to rain destruction on the world. Louisoix attempted to invoke the Twelve to reimprison Bahamut but failed and he was left with no choice but to teleport those adventurers remaining on the battlefield to safety, casting them out of time until it was safe for them to return, resulting in them arriving 5 years later after the realm had begun to recover from the Calamity (this is how 1.x players got to a Realm Reborn and is also the reason nobody can remember what the Warriors of Light looked like). After this Bahamut unleashed its power on the battlefield and looked set to do so to the entire continent but was stopped by some unknown force. Louisoix's body was never found and they could only recover the fragments of his staff from the battlefield.

The general aftermath of that event is that the game got shut down. The Calamity was the event which coincided with the shutdown of the original FFXIV, with A Realm Reborn launching 3 years later. In universe it has been 5 years and it's now the year 1577 (alternatively the 5th year of the 7th Umbral Era as the 6th Astral Era ended with the Calamity). With the brunt of the Calamity having been stopped Eorzea has been moving along the road to recovery and the Empire has largely ceased its ambitions towards the realm for the time being, which is the state of play at the start of ARR. The exact specifics of what happened to Bahamut are unknown at that point (although the level 50 raid series "The Binding Coil of Bahamut" will explain a lot of that but I'm trying to avoid spoilers here since you're new and just stick to background context).

3) the Guy in Ul'dah is Thancred, he was a member of the Circle of Knowing, the tatoo is the Archon's mark which all Sharlayans who have earned that rank are given. Archons are basically extremely acomplished in their field of study, there are more as of yet unspecified requirements but the gist is they're a big deal in Sharlayan. He was in Eorzea at the time of the Calamity but didn't fight at Carteneu as he was elsewhere helping to prepare for Louisoix's summoning of the Twelve (if you rewatch the cinematic he's briefly seen praying at the Ossuary in Ul'dah after Bahamut breaks free). He's now a member of the Scions of the Seventh Dawn, an organisation formed from the remnants of the Circle of Knowing and another organisation called the Path of the Twelve.

4) Primals are unable to temper those who have the Echo, a relatively rare power which the player character has. In addition to the echo though we have the Blessing of Light, which was conferred to us by the Mothercrystal Hydaelyn, which may be what Ifrit is refering to here, we're already "tained by the light" so to speak so Ifrit's tempering cannot afflict us.

5) Paladin is the only option for Gladiator. Worth noting is that the JP name for Paladin is Knight and that more closely fits the flavour of the job. The lore behind the Paladin (as we learn it) is that the Sultansworn Paladins are the sworn defenders of the royal family of Ul'dah. However as the authority of the Sultanate has been erroded by the Syndicate the prestiege of the order has fallen as well, leading to a dwindling of their numbers, which is why their captain is now actively reaching out to talented adventurers (like ourselves) in order to pass down the order's techniques so that they aren't lost.

There's a bit more to most of these answers but as I said I don't want to outright spoil things so this is the general "as things were known to be at release" version of a lot of events.