CPU Cooked? (A300d-013)

I've had my laptop for about two years now. And i have always suffered from my fan/cooling fins plugging up with dust and over heating. My laptop idles at about 85 degrees Celsius(may drop to 70 after a cleaning for a week or two), and blue screen after playing blue rays or gaming(hits close to 100 degrees).
I have blew out the fan numerous times but i think its to the stage to disassemble my laptop and clean. The question is should i replace my processor(if possible on a laptop)? (and heat sink?) It does not work as well as it use to(even after blowing out & formatting HDD).

If i should replace it does anybody know the amd part# for this laptops cpu
or even a upgrade cpu?

Laptop is a Toshiba A300D-013 (PSAKCC-01300Y)
Thanks

Ps: I've only dissembled a laptop once, but i am quite familiar with desktops.