Where should a flagpole be placed on a house?
For most homeowners, the above ground height of the flagpole should be approximately the height of the roof peak. Typically, most homeowners do not want the pole to tower over the house. Other mitigating factors include the slope of the lot and the distance from the flagpole to the house.
Which side of the door does the American flag go on?
It is traditionally flown either to the right or the left of the front door. It can be on either side. When there is a choice, find a position of prominence. Sometimes that is the left of the door, sometimes the right, sometimes away from the door, but centered on the house (when you have a porch, for example).