1. reinstall java runtime environment
2. reinstall flash and shockwave
3. If you have installed any windows updates in the last three weeks, go to your system restore and pick a date before those windows updates were installed.
4. Alternative to number 3, find someone here (in the computing forum) who can step you through working the firewall component to windows xp service pack 2.
5. To update your firefox software, just go to
http://www.mozilla.org, find the link for "firefox browser," and install the latest version.
Combined, those oughta sort you out.