Hey SZ,
i work with both, 8052 family and PIC.
I think when you will start to learn about a microprocessor take 8052.
Because you will learn a real arithmetic core with real C(carry) and Z(Zero) Flags.I think it is realy important for a beginner to understand this.
So you have the best chance to go to bigger CPUs. All the most cores have Register and a Accumulator.

The PIC has only a working register and support the Flags in a different way.
But the Hardware I/O PINs drive more current.

Sascha