the GTX 260 is from the 200 series from nvidia, the 820m is from the 800m series which is newer, and have the "m" which stands for mobile, that only works for nvidia and not all brands. The Q6600 is the core 2 quad which is old too, newer models come as i3, i5 and i7 for normal desktops. Intel CPUs now have the 2xxx (Sandy bridge) , 3xxx (Ivy Bridge), 4xxx (Haswell) and all three generation has different processors i3, i5, i7. The higher the number the better the processor. you have the 4210u which is the mobile or laptop version which is a low voltage lower profile, and there's the 4200m which is also a laptop version but stronger one. There is also desktop ones without the "u" or "m" 4400 up to 4670 which are all i5 cpus, and then the i7 4770, 4790 which is the strongest of the Haswell processors. They also come as a K version like the 4770k, k means the processor can be overclocked to higher speeds.
There is also AMD Processors and Graphic cards, i'd explain them for you if you want