Guys, I am a newbie here and a totally newbie in Linux World, so I need help with my new-built Proxy Server.

I used Windows XP for my previous proxy server and I used WinGate for my proxy filtering user, and to create mail-port dividing. What software should I use for Linux? (I use Mandriva 2006)
I tried Squid, but it couldn't run and it shows nothing but error (something about visible hostname, which i added on squid.conf), started the service, call the program, squid. nothing happened.

Another one that concern me is I used Symantec anti Virus Corporate Edition on my Win XP server. That's a good software I think. I only need to update my virus definition on my server, and my clients automatically updated in a period of time. I also can manage user groups and schedule the weekly scan on my clients.

So, do you guys have recommendation(s) for softwares like mentioned above? If you do, please share it. Thanks.

I run Endian Firewall on a PC here that acts as my router/firewall/proxy, works well. It's based off IPcop so that would be my first port of call as it comes with everything you need already set up