RealTemp is similar to Core Temp but RealTemp can read and display GPU temperatures as long as the video card driver you are using supports that feature.
RealTemp 3.70
http://www.techpowerup.com/realtemp/
The Core i3-2350M has 2 cores and also supports hyperthreading so each core can process 2 threads at a time. Make sure the Task Manager shows 4 graphs, one for each thread. You can also double check with CPU-Z. It should show 2 cores and 4 threads at the bottom.
Some Acer laptops have performance throttling issues. You might be interested in giving ThrottleStop a try.
ThrottleStop 6.00
http://www.thedigitalhq.com/downloads/