The survivors are still dealing with the aftermath of the crash, trying to gather food and supplies. While fighting to keep the dying Marshal alive, Jack discovers Kate's criminal past.
When Sayid, Shannon, Boone, Kate, Sawyer and Charlie agree to keep the news about the French transmission a secret from the rest of the survivors, it's a interesting reflection of the future: when the Oceanic Six will choose to keep what happened on the island a secret from everyone else in the world. Oddly enough, Kate is the first person to break the lie in both instances (telling Jack about the transmission, and telling Claire's mother about her daughter).
We get our first hint of Walt's "specialness" here. Michael promises once it stops raining he'll look for Vincent, and Walt looks out of the tent -- and it suddenly stops pouring.
The demise of the Marshal is very dramatic, both with Sawyer's failed attempt at killing him and Jack's final act.
Hurley didn't want to go into the fuselage because of the dead passengers inside. Hurley may already aware of his ability to talk with the dead and wants to avoid any opportunities for them.