I'm not sure what the other members are up about but defragging will definitely help a system run better. XP's defrag program probably just didn't run correctly as always, should be using a third party program such as smart defrag, defraggler or auslogic disk defragmenter. That may explain why it finally worked on the XP system but there is no explanation so far on why it won't run on the other systems.
Defrag will definitely help a system run faster, but I wouldn't think it would fix a specific game not launching.