Hi Ryan,
The 16 ft length x 12 ft width room is too small to fit the screen and seats specified, for 110" 16:9 (W 96" x H 54" OR W 2435mm x H 1370mm) projection screen and two rows of 3 seats I would go for the second room option with 14 ft wide by about 17 ft deep. this option you will feel more space, have the option to choose the screen mounted on any wall (considering doors, windows and enough access etc) and allow more room for the seats and equipment cabinet. this is also taking into account the sound system, that will allow you to fit 5.1 and 7.1 speaker layout (for 7.1 you will need more depth) and use multiple subwoofers for bass management. for the best sound you might want to look into AURO 3D (personally prefer over Dolby Atmos).
If you like to know more about the screen size calculation this is a good rule of thumb
What is the 2 to 6 rule?
The 2 to 6 Rule is an accepted industry standard that assists in determining the best size projection screen when multiple row seating is in play, such as boardrooms or cinemas.
As follows:
The closest viewing position should be no more than 2 x the height of the screen, with the farthest viewing position being no less than 6 x the height.
Example
The closest viewer is 3m away from the screen, and the furthest viewer is 8m.
3m divided by 2 = 1.5m Maximum Screen Height
8m divided by 6 = 1.3m Minimum Screen Height
Hope that helps
Cheers Yariv
www.avsion.com.au