you have "tried everything" it leaves us wondering exactly WHAT you have actually tried.
The problem you describe is often symptomatic of having hardware acceleration enabled. You can EASILY test to see if this applies to you or not by FIRST looking at this link and carefully noting EXACTLY how the little display window looks - http://www.macromedia.com/support/documentation/en/flashplayer/help/help01.html (go ahead and read the info also)
SECOND go to this link http://www.chemgapedia.de/vsengine/info/en/help/requirements/flash.html
You should see some spheres and play buttons. IGNORE the buttons and RIGHT CLICK on the spheres to bring up a context menu. Near the bottom you should see the selection labeled Settings ... - select that and you should see the little window from the previous link. If you do not see the Disable hardware acceleration line with check box you need to click the icon at the bottom left corner of the window. Once there UNCHECK it and then go and visit Facebook or Zynga AFTER closing then restarting your browser and let us know what develops.
I have an HP Presario CQ56, with 64 bit, WIndows 7. But, when I play games at Facebook, or at Zynga.com, my flash continually crashes. Whether I use Chrome, Firefox, or IE, it crashes. This has been going on for over a year now, & I'm really getting fed up with it. NOBODY has any workable solutions. I've tried everything suggested, from Adobe, Google, from CEGamers, Firefox, & not one suggestion has worked. I uninstalled, reinstalled, temporarily shut down my antivirus program, still crashes. And, there are a LOT of people out there who have the same problem, plus there are also a lot of people who DON'T, & use the same programs that I use. Anybody got any suggestions?