I would suggest Updating Firefox to Firefox 5.1 by following these steps Update Firefox to the latest release . I would also uninstall and reinstall Flash because I don't see it here on the list of plugins you have installed. Let me know if this helps.

There is no Firefox 5.1 -- Firefox 5.0.1 was for Mac OSX only. Windows and Linux versions of Firefox weren't updated, they only got a number change for full version downloads.

You don't seem to have Flash installed, for Firefox at least. IE uses a different version of Flash than other browsers use.

1.Download the Flash setup file from here:
Adobe Flash - Plugin version.
Save it to your Desktop.

2. Close Firefox using File > Exit
then check the Task Manager > Processes tab to make sure firefox.exe is closed,
{XP: Ctrl+Alt+Del, Vista: Shift+Ctrl+ESC = Processes tab}

3. Then run the Flash setup file from your Desktop.

• On Vista and Windows 7 you may need to run the plugin installer as Administrator by starting the installer via the right-click context menu if you do not get an UAC prompt to ask for permission to continue (i.e nothing seems to happen).
  

See this:
http://vistasupport.mvps.org/run_as_administrator.htm

Great !! it worked like a dream. A million thanks.

I had been trying to download the flash player by myself and got two different files: each had a different ending install_flashplayer10_chrd_aih and install_flashplayer10_mssd_aih Each time I wanted to install one or the other it told me that only one instance could run at a time. Frustrating.

Your solution was great. Again, many thanks. Ben Stern