If I run totem 2.26.1 on ubuntu 9.04 by double click a file, and then try to go to fullscreen totem closes with out any error being reported back to the end user. I have twinview turned on using a nvidia card with the latest nvidia drivers. If however I turn twinview off everything works fine. I can use VLC to play video full screen, however and I think this might help located the problem. If under preferences on VLC i select Video/Output modules and leave it as default I get exactly the same symptoms as in totem. If i change the videooutput module to X11 Video output, the problem goes away. This appears to happen on all video formats, WMV, AVI, DVD... etc.
I hope you can fix this bug, I've been having this problem since 7.10 but always assumed it would get fixed.
Thank you for taking the time to report this bug and helping to make Ubuntu better. Please try to obtain a backtrace following the instructions at http:// wiki.ubuntu. com/DebuggingPr ogramCrash and upload the backtrace (as an attachment) to the bug report. This will greatly help us in tracking down your problem.