Oh, that's the best part, girls.
I prefer to glaze the ham, and I've used several different recipes. The way my mom always did it was to score the top of the ham, stud it with cloves, and lay sliced pineapple on top. Sometimes, for special occasions, she'd stick Maraschino cherries in the center of the pineapple slices. She then mixed the juice drained from the pineapple with brown sugar, and basted the ham with that as it baked. It's delicious.
I've also used a mixture of Apricot jam or jelly and Dijon mustard. Heat and stir in a saucepan until warm and starting to bubble. Very good, and not quite as sweet as the above.
Another good one we like is a peach glaze. Drain a large can of peach halves, and mix the syrup with 1/2 cup cider vinegar, 1 cup honey, 1 cup brown sugar, and allspice to taste, about 1/2 tsp. Use to baste your ham.
When the meat is almost tender, arrange the peach halves around it, sprinkle with allspice, and cook another half hour or so.
But we don't always glaze the hams. When we get the Big Daddy bone-in ham for Christmas, we just let it roast in it's own fat, and it's delicious.