Whats the difference between intel Dual-Core and Core 2 Duo?

http://en.wikipedia.org/wiki/Pentium_Dual-Core

The Intel Dual Core is its own product line of Intel processors.

http://en.wikipedia.org/wiki/Intel_Core_2

The Intel Core 2 is also another product line of Intel processors.

The pentium dual-core processor is a one of Intel's value or basic processors available. That is why you save so much going with that processor. The Core 2 is the more powerful desktop processor from Intel, hence why you pay more for it.

Here is a review comparing performance between the two: (This is well put together)

http://expertester.wordpress.com/2008/05/30/core-2-duo-vs-pentium-dual-core/

And a forum discussion about the differences:

http://www.devhardware.com/forums/intel-processors-30/pentium-dual-core-vs-core-2-duo-188459.html

I assume you mean the difference like on this inspiron 537 between the two middle models:

http://www.dell.com/content/products/productdetails.aspx/desktop-inspiron_537s?c=us&cs=19&l=en&s=dhs

If you notice next to the processor names is the intel e5200 and the intel e7500. These are the processor numbers you can look up on the internet for futher specifications and reviews.

The E5200 is listed under the Pentium Processor for Desktop on intel's website:

http://processorfinder.intel.com/List.aspx?ParentRadio=All&ProcFam=2841&SearchKey=

The E7500 is listed under the Core 2 Duo Desktop Processor

http://processorfinder.intel.com/List.aspx?ParentRadio=All&ProcFam=2558&SearchKey=E7500

Dual core refers to a processor that contains two separate processing cores. Core 2 Duo is a brand name of a processor which is also in a dual core configuration. This is the short answer. The brand name and the descriptive name match up precisely in this one case.