probably is.
The crashing could be from their ads, or just about anything. the browser is mis interpretting flash, jscript. try uninstalling FF and reinstalling…
then if that doesn’t work. probably wont. run hijack this, see if you have anything stupid running.
if still nothing nothing. it could be something corrupted in a macromedia plugin for FF and IE, you could try reinstalling.
then reinstalling Java.
then who knows…