SnoopZ it does look like Housecall found traces of the infection, and Counterspy is a very good anti-spyware program. If you want one more scan to put your mind at ease I can recommend Ewido anti-spyware here:
http://www.ewido.net/en/
You will need to use IE, as the scan uses Active X to install.
With regard to Zonealarm - it isn't my favourite, but if it works for you its miles ahead of the packet filter otherwise known as Windows firewall
