Glad you asked [:)]
I have a MacOS 10.1 G4 and Two Red Hat boxes.
I am resolving some issues with my ISP, if you want you can check them out at: [url]http://lewistechnogroup.com[/url] once my line is back up.
GodBlessTexas, Muselix and libertyof76 are correct.
FreeBSD is well KNOWN for its security, its supposed to be the best. Ultimately, its still up to you.
As a package, Red Hat is nice as it has a lot of helpful features and some nice packages. It is more user friendly than most if thats what you need. A lot of the others don't have the ease of use, install and maintainance that Red Hat has. Now, this is mostly due to the packaging as well as some of Red Hats apps.
Regarding MacOS, I know you don't have a Mac but its Niiiiiice. Its based off of FreeBSD, it runs very well - I just love it!