CPUID
Get that, it identifies exactly which processor you have. As soon as you have identified it the easiest to do is to go to Tom's Hardware: Hardware News, Tests and Reviews, look up the CPU rankings and see how your processor performs compared to others.
If you don't even know how to check up your CPU ID, and that a Core 2 is dual core by nature, I suggest not aiming for an OC for the time being.
Get that, it identifies exactly which processor you have. As soon as you have identified it the easiest to do is to go to Tom's Hardware: Hardware News, Tests and Reviews, look up the CPU rankings and see how your processor performs compared to others.
If you don't even know how to check up your CPU ID, and that a Core 2 is dual core by nature, I suggest not aiming for an OC for the time being.