I'm American but have lived in the UK for many years. I love love love Thanksgiving.
When you're a kid, you get the Thursday and Friday off school, which is obviously awesome--we did not get half-term holidays.
In my experience, Thanksgiving is celebrated with the whole extended family, and is potluck--I love the food and that everyone brings their special dish, and we all look forward to so-and-so's pie or whatever. It does mean having to drive to aunt-whoever's house but it's great seeing everyone together.
I did not grow up celebrating Christmas at home, being Jewish, but I did spend many lovely Christmas days with friends and their families. IME that day was for immediate family, so you wouldn't have to drive anywhere. Most families in my area had a massive cartoon ham with the bone in, usually honey-smoked or something. No mince pies but they do eat sprouts.
I love Christmas in the UK. Boxing day is a good recovery day and I love that everything is closed on Christmas. I think also because I never got to fully participate in it as a kid and over here it is impossible not to feel included in the festivities because it is such a huge deal.
I do really really miss that in the USA, Christmas season does not start until the day after THanksgiving. You can start your shopping any time but at least you don't have all the ads/music etc until November.