No. SpywareBlaster does not need to remain open for its protection to be
active!
Simply use the Check for Updates feature at least once a week to download
the latest protection (or consider AutoUpdate).
SpywareBlaster adds sites to the Restricted Sites zone, to restrict the
actions of the sites in Internet Explorer.
That's here >>
Internet Explorer | Tools | Internet Options | Security tab | Restricted
sites zone | Sites button
Restricted sites zone: This zone contains sites you don't trust—sites that
you're not sure whether you can download or run files from without damage to
your computer or data. You can assign sites to this zone. The default
security level for the Restricted sites zone is High, therefore, Internet
Explorer will block all cookies from Web sites in this zone.
SpywareBlaster
http://www.sfsu.edu/~helpdesk/os/winos/SpywareBlaster/spywareblaster.htm