They really should be separate questions.  I mean they are two distinctly different holidays with different rules and schedules.    

Thanksgiving first -

There is no church for starters so we already have more free time.  You have to usually get up early and get ready whether you are headed to someone's house or you are hosting.  You figure that you are up between 8am and 9am.

If you are having company - You should have had the table settings all done the night before.  Also most of the food was made or prepared in the days prior.  So you set yourself up for an organized cooking situation after you are dressed all you need to do is cook.  You should be drinking by 10:30am.

If you are going to someone's house - You get up, get dressed, go to the store to get what you need to bring if you have not already.  Your done by 9:45am.  Now you have WAY too much time to kill.  You either start drinking now and call a cab later or you sit there bored to tears for hours.

Alright now Christmas -

This is way more complicated.  A lot of the same obstacles apply to Christmas that applied to Thanksgiving plus one more....CHURCH.  (Assuming you are religious)

My advice.....go to Midnight Mass the night before.  Then you have to deal with presents.  You get up between 5-7am depending upon how excited your kids are.  You sit and take presents in a pile of papers on the floor with your hair all jacked up.  Then you all go back to sleep between 8 and 9:30.  Now all you have to do is shower, get dressed and get going.  You are drinking by 10am.  That's if you id not agree to go to someone's house.

DISCLAIMER - None of the above activities are plans of mine and drinking at 10am on a holiday can often ruin the day for the rest of your family.  These plans are for trained professionals and in no way do I Lou Milano endorse these activities or behavior.