Does the crash take the entire browser down? If so, see Troubleshoot Firefox crashes (closing or quitting unexpectedly), find and paste the crash ids here. If not, then please try Troubleshoot and diagnose Firefox problems.

I thought it was just me but now I see how widespread this probably is. I have 3.6.11 on Windows 7 ultimate N 64 bit (but using the 32 bit browser) and for some time through several iterations of Firefox AND Adobe updates for the past 6 months the adobe flash plugin keeps crashing and I am required to reload the page. This is pages like iGoogle, Gmail and others that use flash.

More troublesome however is that at least half the time Firefox simply locks up beyond any hope of dealing with it and I have to end up using the task manager to kill the process.

BrowseIT:

Your above posted system details show outdated plugin(s) with known security and stability risks that you should update.

• Java Plug-in 1.6.0_02 for Netscape Navigator (DLL Helper)

Update the Java plugin to the latest version.

• http://java.sun.com/javase/downloads/index.jsp (Java Platform: Download JRE)

Do a malware check with a few malware scan programs.
You need to use all programs because each detects different malware.
Make sure that you update each program to get the latest version of the database before doing a scan.

• http://www.malwarebytes.org/mbam.php - Malwarebytes' Anti-Malware
• http://www.superantispyware.com/ - SuperAntispyware
• http://www.safer-networking.org/en/index.html - Spybot Search & Destroy
• http://www.lavasoft.com/products/ad_aware_free.php - Ad-Aware Free
• http://www.microsoft.com/windows/products/winfamily/defender/default.mspx - Windows Defender: Home Page

See also "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked and What to do when searches take you to the wrong search website