I can only add this: Many schools in So. LA, and ALL in the greater N. O. are are closed either Mon., Tues., and Wed or for the entire week.
If you have young children and you have "been there done that" with Mardi Gras, then the logical choice is to head to WDW, especially this year as it is in value season.
When we go, we run in to MANY families we know both at our hotels and at the parks. I will say that overall, I do not think it "makes or breaks" the week but it definately increases the crowds. By how much, it's hard to say.