i take a lesson from the chinese restaurants. they heat their ribs in a salamander and baste as the ribs heat up. i have good results heating ribs at 350-400 on a cooling rack placed on a cookie sheet(both preheated) on the top rack of the oven. works for pulled pork too(no cooling rack) but only from the cold and not frozen state.
Better Days Barbeque
22" Weber Kettle