There are several FREE local security programs and and LAN scanners you might want to append to your list. Some of these have come in very handy for me, at home and at work.

first and foremost, all of the free utilities by foundstone security:
http://www.foundstone.com/resources/freetools.htm

nmap scanner:
http://www.insecure.org/nmap/

ethereal sniffer:
http://www.ethereal.com/

ettercap sniffer:
http://ettercap.sourceforge.net/

and the winpcap library, needed for windows ports of some these programs:
http://www.winpcap.org/

also, for popup blocking, if you are not currently using a browser with built in capabilities (firefox), a little free tool from google can come in handy. with a few configurations, it makes google searches quick and easy, and blocks pop-ups quite well:
http://toolbar.google.com