You neglected to give us enough details. When do the problems happen? Do you get error messages? Crash reports? Some web sites, many? What was Firefox doing at the time?

sc26 said

All of the firefox versions starting with a 3, are useless, constantly freezing and not responding, i am having to go back tto 27 on a daily basis. When are you going to address the issue please. Also, even though i don't have automatic updated, firefox keeps on putting these broken versions on my PC! Never thought i'd see myself typing this, but at the moment, it's as bad as if not worse than internet explorer

It happens about once every 90 seconds, it's not fussy about which website i am on. Firefox was just open on a webpage at the time, and freezing. No error messages, it just take about a minute for it to start to respond again.

What security software (firewall, anti-virus) do you have?

Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/