One question at a time - after introduction of a rooster eggs can be fertile on the second day, however depending on the number of hens, allow the rooster several additional days to ensure he has made it to all of them.

You can incubate eggs during any time of the year, however, during the colder months the chicks will need a higher level of management to ensure they are warm enough. Here is an article about raising chicks, and PNW 491 is the OSU publication that goes into great detail. http://smallfarms.oregonstate.edu/sfn/spg07chicks and http://hdl.handle.net/1957/17467

When planning on storing eggs to get the right amount before you turn on the incubator follow these steps.
1. Collect eggs at least three times daily. When daily high temperatures exceed 85
degrees F. increase egg collection to five times daily. Collect two or three times in
the morning and one or two times in the afternoon otherwise.
2. Slightly soiled eggs can be used for hatching purposes without causing hatching
problems, but dirty eggs should not be saved. Do not wash dirty eggs.
3. Store eggs in a cool-humid storage area. Ideal storage conditions include a 55 degree F. temperature and 75% relative humidity. Store the eggs with the small end
pointed downward.
4. Alter egg position periodically if not incubating within 4-6 days. Turn the eggs to a
new position once daily until placing in the incubator.
5. Hatchability holds reasonably well up to seven days, but declines rapidly afterward.
Therefore, do not store eggs more than 7 days before incubating. After 3 weeks of
storage, hatchability drops to almost zero. Plan ahead and have a regular hatching
schedule to avoid storage problems and reduced hatches.
6. Allow cool eggs to warm slowly to room temperature before placing in the
incubator. Abrupt warming from 55 degrees to 100 degrees causes moisture
condensation on the egg shell that leads to disease and reduced hatches

Please don't hesitate to contact me with any other questions. Good Luck!