Hello again,
I am back with results I could find:
tried JWPlayer, which provides solution for playing videos from your own server. Nice, but has no parameter to make it autoplay in fullscreen mode. Moreover it does display its logo overlaid on your video in its free version
went back to youtube, trying to find some way to launch it from the image link in fullscreen mode. There is none it seems. The best I could find and achieve was chromeless mode, which does not fill your whole screen, it just fills your whole browser window. That is obviously not exactly the youtube fullscreen mode. Moreover, viewers may get lost, since the only way to get back to the webpage, from this chromeless youtube player, is pressing the back navigation button in their browsers.
so I re-enabled your jscript which auto-fits videos to full page width - and to solve a problem with 4:3 videos, I have slightly edited iframe parameters, look below.
original code for iframe youtube video embed contained absolute height and width sizes in pixels, width="640" and height="480"
Video fitting script on Listviewer page then fills the full width of the page, but is ignoring the height, therefore enlarged the older 4:3 video so much that it would crop bottom part of it (on 16:9 displays).
My little hack solved it for me. I have changed absolute sizes to relative: width="100%" height="55%"
interesting for me was to find out that if I combined relative height in percents with absolute width in pixels, it also interpreted height as absolute and displayed the video only 55 pixels tall. :D After I have changed the width to relative 100%, it worked just fine.
(cannot post the whole code, because this forum doesn't allow me to post any links, not even within code tags, sorry)
PS: I am already re-rendering the mosque animation to small HD, 16:9 ;) Other 2 animations are unfortunately so old, that they were produced to final PAL resolution at that time, and there is no way (or will) to remaster them to HD