Zone Alarm won't stop exploits like these.
Zone Alarm is good. BlackIce is better and more configurable and co$ts a bit of change. Even if you use a software firewall the best choice is a good hardware firewall such as a personal SonicWall or Netgear unit. DOS attacks can lag down your TCP/IP stack so badly that it causes you many problems (even with the very best software firewall).
Ultimate solution is to have a good hardware firewall as your router AND a good software firewall on your server or workstation as a failsafe. I have both and both combined have protected me from every virus attack to date and DOS attacks fail miserably. I do a lot of IRC and with my Conservative opinions and big mouth I get a lot of them. :)