One of my FAVOURITE holidays! I love the weather at this time of year (best part of fall - leaves all different colours, cool days, no snow yet, apples ripe, aaahhhhh, so lovely!) Also my baby will be almost here. Hurray!
Yep, turkey with stuffing is the standard, and many people also have ham, if they have a big gathering. Mashed potatoes, and whatever veggies you like. (We often do corn, beans, and a salad). Pumpkin pie is also the usual, (we do it with whipping cream) with apple probably being a close second.
As far as decorations go, our family doesn't really go too crazy there (there's enough work just getting a meal together for 18 people) but you could use coloured leaves, pumpkins and gourds, corn stalks (don't know where you'd find that by you at this time of year) fall chrysanthemums, "Indian corn" (corn with coloured kernels), anything red, orange, yellow, and brown.
Have fun with it! As the PP mentioned - think fall, and harvest! It is a celebration of God's blessing on the land and crops.