I had recently been running my website through XAMPP via Windows XP. I had just switched over to Lubuntu and setup and installed LAMP. Now, I have always been fond of Ubuntu, Debian, CentOS, and Ubuntu Server. I just never thought Ubuntu could be used efficiently as a desktop and server at once. Well, it is. While running XAMPP I had 300MBs of RAM usage annexed to the already 400MBs being eaten up by XP. Now with Lubuntu I am stabilizing around 352MBs running LAMP. My server load speed according to GTMetrix went down by one second.
I HIGHLY recommend converting to a Linux distro if you run a web-server or any other server.