Preparing to download Avast

I want to download Avast and try it, have read & been told to uninstall current antivirus programs. However was also told to BE SURE to turn on Windows Firewall, but I have looked in control panel and do not see reference to that. Am using Windows XP, can anyone advise???

Hi sclare,
Welcome to the forum and avast!
The firewall is located in the Security Center see below:

http://img84.imageshack.us/img84/3110/firewall6xu.jpg

http://img81.imageshack.us/img81/4948/seccenter5xm.jpg