PC hardware: Processor Specifications Help needed

Processor Specifications Help needed

I was looking at these two mobile processors and all these questions started popping into my head. If anyone could please answer them in layman's terms, I'd be very appreciative.
First of all, these were the two processors I was looking at.
http://ark.intel.com/Product.aspx?id=40480&processor=Q9000&spec-codes=SLGEJ
and
http://ark.intel.com/Product.aspx?id=37033&processor=Q9100&spec-codes=SLB5G

and here are the questions:
If the speed of the processor (in GHz right?) is 2.00GHz, is that per core?
If a dual core processor is 2.50GHz and a quad core is 2.00GHz, is the quad core still a lot faster?

How much of a difference between those two processors is there in speed? I'm not sure what exactly "# of transistors" and "Die Size" and "L2 Cache" are or do, but the Q9100 has twice as much as the Q9000. Would that mean it's a WHOLE LOT faster?

I'm kind of looking for what particular specifications affect the speed and power of the processor the most. I have very little knowledge about CPUs but I'd love to know more. Please fill my brain with knowledge!

Jonathan