A local columnist at AnnArbor.Com is out with a beer pairing article for Thanksgiving.
The fooodie web-site Epicurious points out:
Beer may actually be more food-friendly than wine is. Winemakers, after all, have one ingredient to play with: grapes. Two, if you count wood barrel–aging. Beermakers, on the other hand, can experiment with barley (which adds sweetness), hops (which provide bitterness), yeast (which lend that characteristic "bready" flavor), as well as spices, nuts, chocolate, fruits, and vegetables.
Why I'm highlighting AnnArbor.com article is that many of the beers he's recommending are Belgian. Because he didn't provide a full "Belgian Thanksgiving Dinner" pairing, here are some more suggestions for your plans. Just think how much fun you'll have educating family and friends (as well as the 'research' opportunities for you!)
Before dinner: Roman brewery's Sloeber or Bavik Pils will start you off right - light but with some flavor
Appetizers: He mention's Saison Dupont but another option could be Bavik's Wittekerke or Wittekerke Winter White or Kapitel Blonde (a single Abbey Beer).
Salad course: This is where wines will let you down. They don't have the ability to counter the oil and vinegars of the dressing. Suggestions include: The Wittekerkes or Silly Pils (a little harder to find although we have it on draft)
Entree: He's got these covered with either the Westmalle Trappist Tripel or Orval Trappist Tripel although VSB's Piraat or Monk's Cafe Sour could well counterbalance the variety of flavors for a better complement
Dessert: VSB's Gulden Drak would be stunning with any chocolate desert or cherry pie or Bavik's Petrus Dubbel Bruin would also complement a sweet dinner ending.