What is the CPU? What is the MB and what is ambient temp? It's probably one of the following:
Unless your room temp is 50 °F, I wouldn't trust that "Core" temp value at all. If you have a dual core chip, it could be that your MB temp isn't displayed. If you have a single core chip it's one of those "temp1" numbers probably. What happens to them if you run orthos? One should shoot up if single core, and both should shoot up if dual core. Your MB temp shouldn't be over say 45 C unless you have a serious problem.