I take it by "cinema" you do not mean DCP cinema, just DVD / Blu-ray?
Most cinema professionals will tell you that you should have separate systems for cinema and PA, but most of these these guys still think that PAs are what they were two or three (or more!) decades ago.
The important part of cinema speakers is voice intelligibility, and thus you need speakers that are good with voice. Ideally, you want a single driver that covers the important frequency range of 300 - 3K, which is why traditional cinema speakers have a physically large horn, to go as low as 300Hz.
If you cant get the vocal range on one driver, then the system needs to have decent phase coherence over that frequency range. I note that folks who have chimed in above are using Danley for this application, and given the little I know of their systems (and having never heard one) I suspect they are an excellent choice.
Given the QSC have entered the cinema market and have some damned fine products that are very well regarded, I'd get on the horn with them and see if their products will do both jobs you need well.
Surounds: in this digital age the surround channels have become far more important than they were, and thus the surround channels should have the same voice as L/C/R, or as stuff pans around it will sound shit. There are also more surround channels becoming popular, so wire the surrounds so you can have four channels of surrounds (ie side and back separate) should you want to have 7.1.
Subs: subs should go down to 20Hz or a tad lower if possible. Whether you want to run them for PA that low is a matter of judgement.
Finally: you'll want to read
Dolby Technical guidelines for Dolby Stereo Theatres, available as a PDF (3.7MB) for download from
Film-Tech, or
read online in sections. And note it is from a long time ago, but at least its a start in the right direction.