1) Intel Pentium Dual-Core T2060 1.6GHz - Is a centrino duo based upon the Intel Core Duo chip. (centrino is a mobile version of the chip/chipset optimized for battery life etc, and has wireless built in)

2) Intel Core 2 Duo T5200 Processor 1.6GHz - centrino duo based on Intel Core 2 Duo, the newer chip/chipset.

the 2000 series are core duo, 5000 series are core 2 duo (2MB L2 cache), and the 7000 series are the Core 2 Duo's as well (but with 4mb L2 cache)

so the 5000 is better than the 2000, but the 7000 beats them both

Most of them are badged as centrino nowadays cos they do fancy things with power management and wireless etc. the Core Duo/Core Duo 2 is just the name for the processor itself