Firefox unresponsive due to lock files, how do I remove them?

As my laptop hard rive was knackered I was adivsed to use ubuntu, it set-up perfectly. But i tried downloading Google Chrome and Flash Player because I couldnt watch any videos and now Firefox has become unresponsive.

It says

Firefox is already running but it is not responding. To open a new window, you must first close the exisitng firefox process or restart your system.

I tried restarting but that hasn't worked.

Ubuntu also asked me if i wanted to do a update which I did, could this be a problem also. When I try to delete the files, it tells me the following:

The link ''lock'' is broken. move it to the rubbish bin.

This link cannot be used, because it's target '127.0.1.1;+1885'' doesn't exist

• Killing the process does not work either.

Open the file manager and press Ctrl+H to see hidden files. GO into .mozilla->firefox and there should be one folder in there, possibly with a very weird name. Now, go into that folder and delete the files lock and .parentlock to allow Firefox to access its SQlite database.

Open a terminal (most likely with Ctrl+Alt+T) or use the dash).

Sometimes the process ID will change by the time you copy and paste it. You have to kill Firefox in single instance. Try this script

ps -aux | grep firefox | awk '{print $2}' | head -1 | xargs kill -9

or more simply

killall -s KILL firefox