Christmas Eve was on Sunday in 1950 so that would mean that Christmas Day was on a Monday.
Christmas Day was on a Friday in 1970.
It was a Tuesday.
Sunday
Thursday
Christmas day fell on a Thursday in 1986.
Saturday
Wednesday
On a Monday
Monday
It doesn't matter. Christmas Day is not influenced by the day of the week it is on. It always feels the same, no matter what day of the week it is on. So whether it is on a weekday or a weekend, there is no difference. So no day is best for Christmas Day to fall on.
Leap day does affect which day of the week Christmas falls on, but Christmas will always fall on the 25th. Hope this answered your question!