Hmm, I would probably still attempt to level up a charactor as fast as I can just to see the challenges there within the first couple hours. I would make a random character that I otherwise wouldn't play in a serious setting but play it to the best of my ability to get an idea of whats to come when I play more seriously as a Tank class.
Create my Paladin and go out exploring. The game is promoting itself to be an adventure, so I would want to eperience as much of that within the time frame as possible. Also testing out my toolkit and the many systems like combat AI, perception, crafting etc.
I would probably be in overload mode because I'm trying to do everything at once...lol
If I am dropped in a starting city I would check to see if it is populated with NPCs. Hail every NPC to try to gain information about the world and climb pretty much everything.
If the cities are largely vacant of NPCs and lore sources then I would probably run around as a monk and play with combat mechanics.
Warning, if a background NPC yells at me for climbing his book case, just try taking the game away from me after only 2 hours :D.
I don't want to spoil the 'newness' of the world for myself, so I wouldn't do much sightseeing. Mostly I'd explore options for the characters I want to play at launch. I already have a plan on which Race I'll use for each Class, but not having been ingame yet means those plans are only tentative. So I'd go create versions of each Race that can be a particular Class I want to play. I'd compare their starting stats and gear, and look at the resources available in their starting cities. Since I plan to play 5-10 different Classes, this could easily use up my 2 hours.