Here I am attaching the floor plan. Look for the bed 2 which i would like to convert into theatre room.

Hi, Are you going to be concerned about noise attenuation coming from the games / home theatre room to the rest of the house? As solid core doors will work better than hollow core when closed at reducing the sound transmission. Sealing the door frames and adding ceiling baffles will help further but would need to be considered at the design stage not as an after thought. The solid doors by themselves over hollow doors may drop the STC rating by 6 to 8dB which is noticeable. Andrew

Yes, bigreader, we do. We're thinking we may need to replace it and are trying to figure out where to start.

a raised floor will make the room very cramped as there would need to be space for seating plus a walking path then a step..as bigreader says it will be much better with a comfy couch ..how many people do you need to seat and why does there need to be space taken out for the garage entry..is there no alternative??..a plan of the whole house would help understand the floorplan better