can't uninstall firefox

While using firefox 4 browser, I searched for a google image and (as has happened before) opened up one of those fake antivirus programs instead of an image. When will I learn to stop using google image searches? As usual, I tried to shut down firefox (which has always worked before), but this time I was unable to. I opened the task manager and shut it down there, but when I tried opening it again it reopened the closed tabs, including the fake antivirus. The next thing I tried was a system restore, which failed. Next I tried deleting all mozilla firefox files in safe mode. Same problem again. Then I tried a system restore in safe mode, but when I tried opening firefox in the newly restored system, I got the same problem again (miniturized corrupted firefox window, with old tabs including fake antivirus). Next I tried an uninstall, but that hung after starting. So I tried another uninstall in safe mode, which at first wouldn't open, but after another system restore did, but ended up hanging as well. I am now attempting to use the revo uninstaller, which has been running for two hours now. Fingers crossed.

Install, Update and run Malwarebytes, if necessary in Safe Mode.

Instal, update and run a Full Scan with Microsoft Security Essentials after uninstalling your AV.

Install CCleaner, on Applications tab select all choices for Firefox cleanup, Run Cleaner.

Tried updated malwarebytes before revo, nothing found. I will try your other two suggestions after revo.

Sometimes the only way to uninstall a program which balks is to reinstall it first.

I have stopped using Revo after discovering that most of the keys and files it "removes" after running uninstall are actually removed anyway by the uninstaller after restart, then any shells left behind are snagged by CCleaner. I think it's mostly wasted motion.

k, I used ccleaner, however after running it zero files were removed. I installed Windows Security Essentials and am running a full scan. When I removed my old av, system restarted, so revo had not completed its registry check, but had uninstalled firefox. So I reinstalled Firefox, and when I tried to start it it said that it was already running and I should close it or reboot. Checked task manager, no firefox in applications, so I rebooted and same problem again! Now I am trying to uninstall using windows uninstall option and it seems to be hanging again. I am hoping for the best with the av scan, but am getting discouraged.

Next try SFC -SCANNOW Command
to see if you have damaged System Files causing some of these problems.

If necessary run from Command Line on DVD or Repair CD so no System Files are running: SFC -SCANNOW Run in Command Prompt at Boot

Windows Resource Protection did not find any integrity violations on the system scan. Still running Security Essentials scan.

It's likely the suspected fake AV didn't have a chance to download due to your quick actions. I'd just keep trying to reinstall then uninstall Firefox and use IE9 for awhile which is quite secure and foils the fake AV from what I've seen.

Once you get back into Firefox if necessary, you can set preferences so it won't reopen tabs or windows once closed.

My second fav browser is Google Chrome, also considered by many to be safest, so I guess I'll use that. Still bothers me that there is some corrupted file on my comp, though.
Thanks for the help.

If the fake AV was not downloaded but just remained within the web page which you closed, then there's no evidence you have infection on your computer if Malwarebytes and your AV have come up clean.

Closing the browse was exactly the right thing to do, although I recommend shutting down the computer rather than risking clicking on anything related to the suspect webpage.

Solution

I mucked around with all the ideas here, to no avail - and finally, simply rebooted into Safe mode (F8) and blew away both Firefox 10 and Firefox 11 Beta! That simple! I couldn't believe it! What an obvious solution!