Don't forget to make your root password as strong as possible, that is not a simple name like 'John' but a string of characters and symbols that would be hard to guess (using %$*# and upper-case and lower-case). This is one of the vulnerabilities of Linux, as once someone has your root password (admin in Windows) they can do anything to your systems - even wiping all the files including the OS with a simple command.
I'm using Ubuntu 6.06, with Firestarter firewall, ClamAV, and rootkit hunter. BTW the only real reason for the AV is so I don't pass on infections to Windows users, through emails or files.
