Intel Core 2 Duo Processor T7500 heat problems

Hello,

I have Sony VGN series laptop and it gets very hot, especially when i'm working with Adobe Premiere Elements, video chating through Skype or even watch HD videos on Youtube. I've downloaded SpeedFan to check temperatures and here is what i got (all units are in Celcius):

System idle: 55-56
Exporting movie to DVD with Adobe Premiere Elements: average 75, max 85
Video chating through Skype gives very similar values: average 75

I am convinced that the thermal parameters should be lower. Am i right?

here is cpu temperature chart, made by SpeedFan, when laptop is working on batteries:
http://img210.imageshack.us/i/chartbefore.png/

...and working with ac adaptor (the moment when ac adaptor is plugged can be clearly seen):
http://img209.imageshack.us/i/chartafter.png/