You may want to look here as this has been discussed many times.

http://www.antionline.com/showthread...erating+system

or here (a poll and discussion started by HackerDan) http://www.antionline.com/showthread...erating+system

or here for a discussion about which OS is best for you http://www.antionline.com/showthread...erating+system

and lastly a bit of a server discussion http://www.antionline.com/showthread...erating+system