Can I cook ribs for about 2 to 3 hours, wrap them in butcher paper and set aside. Then go to church (say 2 hour pause) and either finish in smoker or oven.

Another option is to just get up earlier - cook them fully and warm them up later.

I will also be cooking a sliced bone-in ham too. It's fully cooked and just needs to heated up. It will take about 2 hours. I will have a house full about 2 hours after I get home from church. I just want to have everything done at the same time.

Sure. Why not?

My concern is drying out. I will see what happens

Why not wrap and then finish in oven and then when you get back you can eat immediately if you like fall off the bone ribs or put them back on grill or smoker unwrapped if you want to tighten them back up a little.

Ive cooked ribs late the night before, 1-2 hours per side unwrapped. Then wrapped them and put them in a cooler and let them sit over night. Woke up the next day and thrown them back on the pit wrapped for about an hour each side and they turned out fine.