Firefox exiting when attempting to access certain web sites

[David W. Florence]

Greetings all, first post to the list.

Been having this problem with Firefox shutting down when going to some 
of my regular web sites. Have done several reinstalls of  the browser, 
even several clean installs of FC5 x86_64, without any success. The last 
attempt was successfull, for a couple of days, then it reverted back to 
it's bad behavior.
Any ideas how to correct the situation???