Really need help with 4 year old laptop

[SpartenOmega117]

I purchased the inspiron 6000 4 years ago. It has an intel centrino processor and only 512 mb of ram. Im thinking about upgrading it a little bit. First of all does anyone know a proper way to install the ream? Also 512 mb of ram and 2gb of ram make a significant difference since it the the intel centrino processor?

 

thanks in advance