I also would suggest:
1. Manage the browser using the add-on or application manager - Internet Explorer, Firefox and Opera let you manage the add-ons of your browser. You can use the add-on manager to update, remove or view who owns the add-ons. This allows you to determine if the add-on is needed and legitimate.
2. Protected Mode – Internet Explorer in Vista includes Protected Mode feature and it is enabled by default. Take advantage of this feature to restrict changes on system and browser.
3. Privacy matters – Browser keeps our private information (password, username, credit card etc). Most browser has options to deal with this information prevent identity theft, targeted advertising and fraud.
4. Reset Tools - Firefox includes Safe Mode feature. While this feature of Firefox is built to troubleshoot, a user can use it also to get rid of the bad or rogue browser add-ons and by resetting the browser to its default state. Internet Explorer offer also this feature by providing a reset and restore options.
6. Anti-Fraud and Anti-Malware – Firefox offers Web ID, anti-malware and anti-fraud protections, Internet Explorer offers anti-phishing while Opera offers anti-malware and anti-fraud protections. Enable these options to avoid visiting sites that will infect your computer and steal information.
7. Certificate settings – Before making any transactions using these powerful browsers, you should ensure to identify the certificate and that it is verified.