Core Temp will show you a lot of data even on the default screen, mainly the different temperature readouts from each CPU core, but the CPU #0 figure is the temperature you want to monitor.

Basically I'm trying to read my 8800 GT's temp from a display on my laptop over a local network. I am using Core Temp for CPU temps (works pisser- I just wish there was a GPU temp plugin for it ...

CPU temperature is the temperature of the actual chip itself, and it runs quite high, with some modern CPUs reaching up to 95-100 degrees Celsius (203-212 degrees Fahrenheit).