Firefox not starting

For some reason, my firefox isn't opening. I click on it and nothing happens. I go to windows task manager and see that it's running but I can't see anything. The only problem I can see causing this is that I updated my downloadthemall extension a few hours earlier (and it ran fine then). Anyone know how I could fix this?

Start Firefox (not Windows!) in safe mode and disable the problem extension.  Close and try again.  The Firefox safe-mode icon is in your start menu.  If you removed it or don't have it, the command is: firefox.exe -safe-mode

You've been raped by this problem?
http://packetstormsecurity.org/0512-exploits/firefox-1.5-buffer-overflow.txt
http//news.com.com/...