You can report sites by selecting "Report Web Forgery" in the Help menu. This can be used for phishing sites, suspect attack sites or sites that you believe have been infected with malware/viruses. Google maintain the list of reported sites and will check the site and consider adding it to the list of suspect sites.

See also AlertCheck: https://addons.mozilla.org/firefox/addon/13176/

Firefox 3.5 and later versions will automatically try to restore the tabs and windows from the last session if a crash has occurred or Firefox wasn't closed properly the previous time.

Set the pref browser.sessionstore.max_resumed_crashes to 0 on the about:config page to get the about:sessionrestore page immediately with the first restart after a crash has occurred or the Task Manager was used to close Firefox.

That will allow you to deselect the tab(s) that you do not want to reopen, but will allow to reopen the other tabs.

See:

• http://kb.mozillazine.org/Session_Restore#Restoring_a_session_after_a_crash