Pentium is just a brand name, and one that Intel are gradually dropping. For the last couple of years they have been using the name for their mid-range cpus.
None of the cpus in your questions are Pentiums. Not sure what you mean by "the processor below".
The Core 2 Duo was the name for their "top of the range" cpus, but that is being dropped in favour of the i3, i5, and i7 cpus.
For all sorts of technical reasons I wont bore you with you are better getting a i3, i5 or i7 (they run cooler and use less power are two good reasons).