Firefox keeps experiencing problems?

Hello I am running a XP SP2 1 GB RAM P4 2.8 GHz and I have a few free light security software on my computer including (Spyware Blaster, Avast AntiVirus, ADAware SE, Pc Cillin Internet Security [The Updates have expired so now I use it mainly as a firewall])

On an occasion when I am browsing a window appears saying firefox has encountered an error and needs to close. Coinsidentally it happens a lot when I have to firefox screens up or a yahoo mail up. Why is this happening?

If it helps to know I turned Windows Firewall off because it kept blocking my online gaming (Steam - which is counterstrike, cs cource, condition zero....)

Firefox keeps experiencing problems?agv

Don't forget the plug-ins. They sometimes cause problems. Try running Firefox in safe mode (Firefox safe-mode, that is, not Windows safe-mode.) If Firefox runs without any errors, then it's one of your plug-ins.

Firefox keeps experiencing problems?antivirus software

Firefox has released several updates this week, and Microsoft will next week. Also check out Yahoo for updates too if you use their toolbars and Instant Messaging Services. You can set your computer to do these updates for you in some cases. Also why not Microsoft Beta Anti-Spy? And AVG anti virus programs ? They will not conflict with you other programs. And again they like Avast can auto update and run when you tell them too. Also check into WinPatrol. It is free too. And it auto-runs and tells you everything that is running on your system, not just the start up menu. It also gives you free info on them unlike task Manager from Windows. And you can tell your Windows Firewall to let your game run through the firewall. If it has subordinate programs to chat or play on the net you can include them too. But security is the number one thing you should take care of. Updates and programs to fight the threats out there. If you look you will find them free. And the ones I named are not just trials. They are for the life of the license agreement. Finally find an ISP that will block out a lot of the known threats in emails and such. You might pay more, but the peace of mind is worth it.
it's not just firefox. internet explorer does that to me sometimes too. just a glitch - remember, nothing's perfect
Does it happen at certain websites? Sometimes webpages just crash your browser, like Heavy.com. When I'm on a media link site they don't tell you it's a link to Heavy.com so when the window opens and it's Heavy.com I say "DAMMIT HEAVY!" and shut the window and then Firefox crashes. I multitask too much so I'm always switching windows too so sometimes it crashes that way.
Try reinstalling firefox or updating it. It may be doing that because of corrupted browser or outside mallicious access to ur computer. Turn on firewall and see if it helps.. its recommended to keep it on anyways.. if u want to play online games just add these programs and the ports they use to the exception list.
try uninstalling and reinstalling firefox....
These two MS sites should address the error message you are getting.