More Noob Questions....

[Bixby]

1. Change classes to a DPS class (LNC, PGL, ARC, ACN, THM). You're already level 10, so if you've done the level 10 class quest for GLA, you've unlocked the ability to change classes. Visit the guild for the DPS class you want to switch to, do the quest(s) from the receptionist, and go from there. Once you catch up to your GLA's current level, you'll be ready to continue the main quest line as your new class.

2. 20. Though your actual level may vary when you unlock it, as it's part of the main quest line.

3. Pretty much. 4-man (and later on, 8-man for some) parties instead of 5. And you need to unlock each dungeon via a quest before you can run it. And you can't enter them solo. You can queue up to get a random party, or form anything from a partial to full party and let the DF fill in the blanks.

4. Yep. Around level 15 in the main story, you get quests to visit the other main cities, which also give you access to the airship, which will take you from city to city for a small fee. The main story will take you through pretty much every major area in the game.

[Niwashi]

2. 20. Though your actual level may vary when you unlock it, as it's part of the main quest line.

Well, it's not technically part of the main quest line, though you need to reach a certain point in the main quest line to do it. The main quest line has you join a Grand Company, and once you do you'll be offered another quest about getting a Chocobo. The Chocobo quest is actually identified as a side quest, though, since it requires accumulating 2,000 Grand Company seals, which can take a while, and they didn't want to halt the story progression there for that long. I guess that makes it sort of an offshoot of the main quest line.

One thing that isn't made very clear in-game is that getting a chocobo is what unlocks the ability to use mounts in general. If you have other mounts (like the Coeurl mount for buying the Collector's Edition, or the Ahriman mount for subscribing for three months), you can't use those until you complete the Chocobo quest.