Alas, here I am on Christmas Day (Merry Christmas, people)… getting into a tizz because it seems now very likely that I have a serious problem with the screen of the iMac. Apparently the 20″ screens were (and still are) extremely poor quality. Unusual for Apple but there it is. I now have severe banding/streaking lines up and down my screen, and the severity depends on what colours are in use. I cannot get a fully black screen, its like theres a big light behind it, and gauze draped over the top. When applications open, it depends on the colours and gfx. Example below.
The very saddest thing, of course, is that the warranty on the computer was up about July, and I did not buy Applecare to get an extra couple of years. Foolishly, did not think I would need it. Looks like once it dies, it will be trashed.