setting up long runs of hardwood flooring: where to square from?
If flooring is to run into all room eventually and it is a wood floor, start on your longest wall which is usually in the hallway leading to the bedrooms (a sketch would have really helped on this). if the rooms off of the hallway or out of square, the adjustment can be made at the door where the wood floor is the shortest, by tapering that joint in the door by 1/8" in a 32" joint will change the lay of the floor going into the bedroom by a 1/2" in a  10' room. More adjustment can be made by setting the nails harder on one side of the room compared to the other. I have used that technique in "steering" the floor over a long run after the rows are well established.

Any room that the flooring runs into can be adjusted slightly as well without seeing a noticeable curve in the floor. I also have done so much as slightly tapering flooring to aid in "adjusting" the floor going into a room.