I'll bite.
Just so you know, your question is long and has far to much substance to attract much attention, for faster responses in the future, you probably want to break down your posts to individual questions and either stagger the start, or start them all at once. That way you pick up more people who don't have as much time to respond, or are more specialized in individual areas.
Now. Lets break down your post.
Question 1 - 16x9 or not?
You should do 16x9 absolutely. Even if you have to letter box it for now in the projector itself and run every other part of your signal chain 4:3 you should absolutely use a 16x9 screen and projector now.
Question 2 - What projector to use?
The sony is an ok enough projector I would assume, but it wouldn't be my first choice. On one hand its cheap, but on the other hand the output isn't enough that I would recommend it for many applications.
Finding the right projector has to do with mathematical formulas as to how big the screen is, if it is a front or rear projection, and how much ambient light is in the room. Personally for any of the smaller screen needs I have these days I like the Panasonic PT-DW5100U it is a great cost/brightness ratio and has all the right features for an install projector.
This is of course _IF_ it fits your needs and the brightness requirements of the room.
Question 3 - Projector Cabling
You are right in that you want to use RGBHV with a Composite backup. You may or may not need the BNC to HD15 breakout cables depending on the projector you end up with.
Question 4 - Camera Cabling
You didn't ask this as a question, but you should have.
You will want to make sure you run Three (3) HD-SDI compliant camera cables and have an outlet at 3 or 4 "Key Camera Positions" these would be one center stage out in the audience , one about 45* off of center stage out in the audience on either side, and one on stage somewhere.
Something like a Belden 1694A is what you would be going for.
This way you can use one of the cables for SDI if you ever get there, or you can use one of them with a line driver for composite, 2 of them with a combiner cable for S-Video or 3 of them for Component.
Question 4 - The Software
Ask 10 different people this question and you will get 4 or 5 different answers. What do I mean by this? - You have your choice here, but there aren't a lot of _good_ choices.
While some people here will disagree with me, I think that most people should stick to one of three packages.
On Windows there is EasyWorship and SongShow Plus
On Mac there is the Renewed Vision Products
Any of these will do 16x9, Motion or Static Backgrounds, Video, and DVD playback.
I am partial to the Renewed Vision products on the mac myself, but have used the other two with success.
The only issue with Renewed vision's products is that it doesn't natively bring in a ppt file. To get around that they have made sure it plays nice with powerpoint running on the same machine as their products and we have come to prefer this process as it lets us use powerpoint to project powerpoint, and that just seems to cause less problems for us.
Question 5 - Powerpoint / Keynote and stretched stuff.
I will share with you a secret - we have stretched our powerpoint _and_ keynote for a long time and it works just fine, all of our guests coming in we do that with and none of them have ever noticed.
That said, Keynote or powerpoint can do 16x9 very easily, In keynote just select a 16x9 resolution, in powerpoint just go to page setup and change it from 10x7.5 to 16x9
Question 6 - What machine does what
First off, you can do pretty much everything you have talked about from a single machine. Powerpoint, Lyrics, Backgrounds (static/moving), video file playback and DVD playback.
The upside to this is cost. You don't need two machines, you don't need two sets of software, you don't need the scalers and keyers (more on that in a minute). You also don't need multiple people to run it, and you don't need much space
The downside is this can be very limiting in your workflow potential, It doesn't promote a team mentality and depending on how much media you do it can be counter productive to try and have one person pull off all of the cues.
If you can afford it, I prefer to see multiple machines and a separate scalar/keyer as the quality potential is exponentially increased.
If you do use different machines, let one of them run only backgrounds or video files, let the other do your sermon notes, powerpoint, lyrics projection, etc. Then since you will have a switcher/scalar/keyer go ahead and use a dedicated DVD player as those always work better than a computer.
Question 7 - To Play DVDs Or Not?
There is a few ways to go about this, you can play a DVD back in a worship program such as those mentioned above or you can rip the DVD to the computer and play the file back, or you can use a real dvd player.
Personally, If you are just watching a DVD, I am all about a DVD player. If you are cueing a DVD, we rip it to a file.
Legal Statements Apply, Etc.
Question 8 - What Magic Makes All This Come Together?!?!
This, my friend, is called the switcher scalar. While simpler ones just switch and scale, more advanced ones switch, scale and allow you to do effects such as keying.
From what you are describing I would take a look a really hard look at the new Barco DCS-100 or its FSR counterpart. It is reasonably priced for the quality bracket it is in and would let you do some great things such as seamlessly transition from one video source to another as well as have a native resolution DVI DSK that is unheard of in this price bracket. This would let you have words up on the screen and underneath them fade between a camera and a video from your video machine or put text over a dvd, while transitioning to a computer background etc - etc. Plus all of this can happen without the projector ever putting up notices on the screen or going blue.
Hope some of this helps,
Karl P
TeamLeader.TechnicalSystems - churchatchapelhill