I would recommend you check out the 2.35 forum on AVSforum to get the full background, but I'll try to help a bit. When watching 2.35 movies on a 16:9(1.78) screen, as you know, there will be black bars on the top and bottom. As a result, 33% of the panels (pixels) are not being used.
To resolve this you must first use a scaler to vertically stretch the image to fit the height and reclaim those lost pixels, but leave the width alone. This will make everything look skinny. Many people use HTPC's with theatertek software to perform the scaling, however some projectors and DVD players will also achieve the needed stretch. A benefit of using the full panel is that you will increase brightness by as much as 20%or more.
The next step is to reshape the stretched image into the needed 2.35 aspect ratio, to fit your 2.35 screen. This is accomplished by using an anamorphic lens. Prismasonic, Panamorph, and ISCO are the most popular brands. There are vertical and horizontal type lenses. I prefer the horizontal types as it takes my image and horizontally stretches it back out to fill my screen. I can achieve a huge image from a relatively short throw distance. Vertical lenses basically do the same thing, however, they vertically squeeze the scaled image back down to create a 2.35 image and a smaller screen from the same throw distance.
I have a Z2 and a Prismasonic H600 lens and I will never go back to 16:9 screens. There is nothing like enjoying movies as they were intended to be watched in the theaters.
This is called a constant height setup. The height stays the same always, the only thing that changes is the width. It is much easier to mask the sides for 1.85 and 1.33 material, than it is to mask the tops of the screen, just use curtains like they do in the theaters.
Now the Z2 will only vertically stretch 480p material, however, the newer Z4 will perform the needed stretch on 480p, 720p, or 1080i, so I've got my eyes set on the Z4 at some point. There are other projectors that will do the needed stretch, as well as DVD players, and high end scalers like DVDO or HTPC's.
Here is my screen image size for various movies:
2.35 material - 51" x 120"
1.85 material - 51" x 94.35"
1.33 material - 51" x 67.83"
A few pics
1.85 movie "Napoleon Dynamite"
2.35 movie "StarWars Episode II"