New Player: Went ROG

[Chrallmal]

The best thing you can do for your party is to know how to do your job (proportional to your level and abilities), and research the boss fights ahead of time.** There are many video tutorials such as MTQ Capture, and Mr. Happy (on YouTube)

As for Samurai, they have no base class. Rogues become Ninja. Pugilists become Monks.

In order to unlock Samurai, all you have to do is have ANY combat class at level 50. Then an NPC will become available in Ul'Dah who will unlock Samurai for you.

Best part - Samurai starts at level 50 - not level 1. So you'd have a level 50 Ninja (or MNK if you went the Pugilist route) and a level 50 Samurai.

** EDIT: If you don't want to spoil your experience in dungeons by watching video tutorials ahead of time, that's fine. Just be on your toes. Lower level dungeons are extremely forgiving because they are meant to teach you how to do your job and work with fight mechanics.