PCB Heaven server runs in Linux. It is (i must admit) harder to setup a full featured server (not that hard using some LAMP version of linux) but i can assure you, with hand over heart, it worths it! I have NEVER NEVER done a restart, it has NEVER NEVER collapse, whenever a new version needs a restart, a very distinctive icon on top right appears and not this stupid annoying windows message "YOUR COMPUTER NEEDS TO RESTART".
everything is ABSOLUTELY free. You can setup a really good full featured server by spending 0 Euro on software. And it will be much better than windows. Especially after windows 2000 that for me, was the only windows version that (somehow) it worked...