I realize I'm a maniac. Most people, if they suddenly learned that there would be 10 people for dinner, would go out and buy a package of chicken breasts or boil up a pot of pasta. Instead of that sensible approach, I rooted through my freezer and hauled out a 5 lb. standing rib roast (that really needed to be cooked soon) to cook for tonight's dinner. It was vacuum packed so I threw the whole package in a tub of warm water - but this only defrosted the outside. Dinner is to be served in about 3-1/2 hours and I'm trying to figure out how to get this thing cooked. I want to do it on the gas barbecue. Should I season it and throw it onto the grill, indirect heat, on low for as long as it takes? Will the insides cook to edibility? Any other suggestions?