Need Advice of CA Internet Security Suite Plus 2008?

I just bought CA Internet Security Suite plus 2008,try to installation 2 days ago, the process
has error,the antivirus Avast show warning sign infection virus/worm found,read back the Start Guide CA Internet Security is said must be uninstall all Firewall/Anti-virus/& Anti-spyware want to know it is worth to remove all,I have been used free Firewall:ZoneAlarm because ZA is compatible w/VisualZone 5.7/Virus AVAST/Spyware I
used Ad-Aware 2008,Spybot S&D,SpywareBlaster,
Spyware Doctor,need help for advice it is worth to uninstall all instead of CA INTERNET Security
any help I appreciate .Thankyou