laminates do creak and sound hollow. does yours have a membrane that you installed on the floor before the lamintes? This will dampen the hollow sound.
quarter round is OK unless you did not leave about 1/4 inch of space all around the perimeter for the laminates to move around. If you butted up to the wall, then this will only buckle later on.
The clicking sound in the closet is because you have a enclosed space and its like an echo. No worry. the room, well, this is it. Furniture and drapes and stuff will also dampen the sound. You will get used to it.