Yes, I did start with a CRT, although I was doing constant height with the CRT, which was a NEC and an external scaler.
Stop thinking diagonal for your screen size. It will only confuse you and really has no meaning in the projection world. Think screen height and width. Multiply height by 1.77 to determine image width for flat movies. Multiply by 2.35 to determine image width for scope movies (and the screen width).
In your 12.2' width room, let's assume you have room to install a 11' wide screen. Dividing 11' by 2.35 gives you a 4.7' screen height. 4.7 x 1.77 gives you a flat image width of 8.3'. Use the 4.7 x 8.3 image size to determine your throw ratio to make sure your projector will work in your room.
Yes, anamorphic lenses are expensive. In this case, $ directly relates to image quality. An anamorphic lens is forever. Get the best lens you can afford. Cylindrical lenses with adjustable astigmatism correction will always beat prism based lenses with fixed astigmatism correction with regards to image quality. Of course, they are also more expensive.
Projectors are constantly being replaced with new "improved" models with better price performance. Yes, DILA is the way to go when you are used to the CRT projectors. Watch out for single chip DLP, I find them to be excessively digital looking and I have issues with seeing rainbows as well.
I hope this helps.