Iceweasel crashes when javascript is turned on

[mfklinux]

When I go to a link (using Mozilla iceweasel) that uses Javascript then click the back button or click on another link I get an error that shuts down iceweasel. This does not happen every time, but almost everytime. This started when I downloaded the latest version of Firefox, thinking it would update Iceweasel, which probably did not happen but caused a conflict. My "about iceweasel" shows version 2.0.0.14. Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv: 1.8.1.14 Gecko/20080404
I need explicit instructions. There is much I do not understand or know how to do.

[craigevil]

What Debian releases are you running? The current version of iceweasel in stable is 3.0.6.

[mfklinux]

Thanks for replying. I don't know what I was supposed to put in the title box, my sign on or the name of the thread.
First, I think I have the problem solved on that. My Debian is Lenny. When I click help and about it shows Iceweasel to be Version 2.0.0.14
I have run Update on apt-get recently. I don't know if that means it should have got the latest verson or not.
What I did to solve the problem was to use Apt-get to "completely remove" everything that looked like Firefox, Iceweasel, other Mozilla browsers, anything connected with Java, Java script and flash and Gnash. Then I reloaded (with Apt-get) the ones that I thought I needed. It cured the crash problem.
I still cannot get flash 10 to work so I cannot view a lot of videos or get youtube videos. I will address that in a later post for help.
I do have two threads out here for the problem (firefox crashes) that you responded to. I am sorry for that. I could not find the first post anywhere so I made the second. Then the first showed up. Thank you for your help. I will welcome any other suggestions you have.