I've flown on turkey day before - no real difference, tends to be pretty low-key in general.

As for which flight to take - since you have to work the next day, maybe it depends on how much trouble it would be for you at work if your flight was canceled and you didn't get home until Friday? If it's not a big deal for you to miss work due to unforeseen circumstances, I'd probably take a later flight if I wanted to spend a bit more time with family on Thanksgiving Day. But if it would be problematic, then I'd look for an earlier flight and one where there was at least one or more backup options later in the day on that airline, just in case.