When I am looking at a processor should I just be looking at the Ghz, or is the cache important too? Is there any other details I should pay attention to?
This will help a bit. Cache simply put is the middle ground where info is held before or after being processed. The standard definition is it is used to lower access to memory.
When looking at a CPU first you want to be able to understand the competition, what task you are doing, and how high the CPU usage will be. Like for gaming, you don't need 6 cores to game, but you want 6 cores to render and such.
It's not all about GHz or cache, but more so cycles per clock TO the GHz and how many cores you need based on the task at hand.
Cache is super fast memory that sits right next to the processor. Information for the processor to process is queued up in a buffer and then sent to the processor, also it's used for commonly used services and such.