aloha from Hawaii - thank you for opening the HT Forum to beginners like myself. #1: I'm considering the BenQPE8700 on a fixed screen. 1.78 or 1.85 or 2.35 - 1.78 is 16:9 but what about the "Letterbox" and "Cinemascope" formats? As I understand it at 16:9 the "letterbox" will get you top and bottom black bars. How do I get all 3 formats onto one screen? Do I need all 3 sizes in one? Can one screen accomodate all? Should I just do 2.35? or am I missing the point entirely? #2 - why is it important to lay a wooden sub floor on a concrete slab? mahalo for listening to this novice and you're all invited to Hawaii upon completion of my HT.