Well, according to the above it is 3200 MHZ (3.2 GHZ). But why is said twice? I have one of those duel processors. I was always under the impression they were called 'dual' because there are two of them, making then ideal for running multiple tasks.
So programs that are written to take advantage of the processing powers of two cores would be able to utilize both cores. And overall you'll be able to multitask better.
It says Pentium D 3.20, which is the model of the processor, then it says the current speed. So if it was overclocked, it should say something like "Pentium D 3.20Ghz, 3.50Ghz"