Let me give it a shot. Anyone, please feel free to add or correct the list.
New Year’s Day: January 1st. Major – Many people also take off the week between Christmas Day and New Year’s Day.
Martin Luther King Day: Third Monday of January. Between a Major and Minor – Many employers close on this day. It is the PC thing to do.
Presidents' Day: It is celebrated on the third Monday in February. Minor.
Memorial Day: Celebrated on the fourth Monday of May. Major – first big holiday of the Summer season.
Fourth of July, or Independence Day: July 4th. Major – If the date falls in the week, many will take off the weekdays before or after to create a “long weekend.”
Labor Day: The first Monday of September. Major – Last big holiday of the Summer season.
Columbus Day: Takes place on the second Monday in October. Minor.
Veterans Day: November 11th. Minor.
Thanksgiving Day: The fourth Thursday in November. Major – Many businesses also close on the next day (Friday) to make a “long weekend.”
Christmas Day: December 25th. Major – Many businesses close early on the 24th also and many people also take off the week between Christmas Day and New Year’s Day.