I will jump in here before the Gurus have a chance. If your GUI looks the same on every resolution and screen size (I assume you are checking this using the AV wizard) then you have a problem. I can tell you from a week of experimenting that the video outputs are very different depending on how they are set. Are you certain you have everything connected correctly? Double check your projectors manual. And then search here for video/modeline. I know there are several threads on tweaking the modeline in the xorg.conf to match your particular video output needs.
I couldn't get any 16:9 resolution to work most likely because graphic card driver.
And as far as the equipment that can be found in a dump, ("almost death" I loved that description) I think you may be missing the point of Linux in general. The computer/software industry makes gazillions by convincing folks that they constantly need the latest and greatest, when in reality they most certainly do not. Linux distros, which for the most part are developed by people who don't want to get into your pockets, take a more sensible approach. Linux works on equipment that is well behind the bleeding edge because that is all you need to get the job done. Buying more than is needed to get the job done ends up only benefiting the hardware companies, not you.
I know, I have done ten's of linux projects with used computes (my first computer, 10 years old, now its used like home
router with IPCop, then juke-box, wireless router, media player with knoppmyth, car pc with imediamythtv/viaepia board...),
but for some thing like this I do not want to use old computer.
by the way, 180" screen is impressive. where are you setting this up? in your barn?
Its in my bedroom, and yes its impressive
, i was thinking to put another one in garage to have my own drive in.