Jade, Vista informs you that you have multiple anti-virus application running. I assume this being Norton and zone security.
First thing to do is to go to Control panel>uninstall programmes and look if Norton is there. While you are there look whether spybot search and destroy is there as well.
If that is the case try to uninstall these programmes from there.
If you cant get rid of Norton (which is likely) go to
click here and follow the instructions to the letter!!
Post back your findings .