Hansel,
For your A/V distribution, consider an in-house cable TV broadcast. This is actually quite simple. You will purchase two items: 1) an RF modulator, which takes the audio and video signals and encodes them as a "TV channel"; and 2) an RF distribution amplifier (DA), which sends out a separate copy of your broadcast to each television via RG-6 coaxial cable.
The advantages of this approach are that it is inexpensive; virtually any television can handle a cable signal; everything is carried on one wire; and your system is easily expandable.
However, the quality is better if you send the original baseband video and audio signals rather than encoding them as a TV channel. This approach is more costly and more complicated though, and for most televisions the difference won't be significant, but if you're using projectors for any of the remote locations you might consider it. If you decide to send the baseband signals, you will need distribution amplifiers for both baseband (composite) video and balanced audio.
Best regards,
Brad
