This web site discusses travel times from Norway to Iceland but it says from modern day Bergen to the Horn of Iceland it would be about three days. I remember reading from a source I cannot remember that from the Telemark area of Norway to Northumbria was about 4-5 days on the sea (3-4 if winds are favorable). Now for 5 days you would have to have enough food onboard but that wasn't a big issue as voyaging ships were bigger than you might think. They would have carried on the ships with them chickens, goats, sheep, and even cows and horses, all of which could be slaughtered, cooked and eaten on the ship. More likely food with long shelf-life like cheese and skate (cold-air dried fish) are items that were eaten in plenty on the ship and at home and would have high protein content giving a good energy boost.

One of the things that gave Viking raiders their advantage was their ability to sneak up on a target and then surprise them. The ships were able to navigate to the shore and up rivers allowing quick/flexible movement. The fact that they had that maneuverability would allow them to choose a land base of their suiting meaning a place that would be safe/defendable but also ideally a good place to scavenge and hunt, thus living off the land as they did back home would be a viable option for procuring food. During the raiding, food items were certainly taken and could further feed the warriors for their campaign or sustain them on the trip home.

I am not sure if there is an answer on how long they would rest up after a trip. That said, since tactics on the raiders side allowed for them to choose their fights, I assume they would of waited long enough until they were ready but not long enough to allow for them to be discovered and lose the advantage of surprise. But you have to remember that Norsemen were physically fit for ship voyages and fighting as their lifestyle required being able to endure demanding physical tasks. Also tests of endurance through sports were a way to test for a man's ability as a warrior (or in the society as being a "proper man", weakness was disdained) The physical work that went into raiding in England was all a part of a days work, I doubt their was much room for stragglers.