Champagne is always right for cocktail hour, but I'm talking about accompaniment to food. As a semi-amateur wine drinker, my advice is to drink whatever you like with dinner, provided that it is red in color. These holidays are not about gourmet cooking, they are about traditional comfort food and so they need comfort wines.
This year for Thanksgiving, I am going for a Brunello di Montalcino Riserva followed up by a nice Chianti Riserva. Why Tuscans, why Sangiovese? Just for the fun of it. Also because they do not overpower turkey and stuffing, but who really cares about that?
Our more mature readers surely remember the cheap and horrible-tasting Chiantis in straw wrappings in spaghetti-and-meatball restaurants. That straw-wrapped bottle is/was called a "fiasco" - a flask. That wine was a fiasco but the bottles made for cute candlesticks.
Well, Chiantis imported to the US can be darn good these days, and the so-called Super-Tuscans (with varying amounts of Cabernet added to the mix) are quite tasty too. The Chianti Classicos and Riservas tend to be tastier than the basic Chianti table wines.
Here's a little info about Chianti.