for O you need a holiday week or prime summer
but, I can tell you, that with kids, xmas is very crowded and hectic (I will NEVER go again at xmas--way too crowded). Also, Easter/spring break varies---so your week might or might not fall on the time when your kids vacation from school--unless they do a fixed week every year (1st week in march, etc.).
Last 2 weeks March are always a good traders, b/c there will always be a school break then, even if it is not Easter week.
For summer, best week is 4th of July (wk 26), then other July weeks. By mid-Aug, many southern school have started back--so only buy a July week in summer.
Bottom line, xmas (wk 52, wk 51 only good trader when xmas falls within the week, which is only 50% of the time), last 2 weeks of March, or july weeks.