Generally, if your laptop's CPU is running higher than 60-65 degrees Celsius (140-149 degrees Fahrenheit), you are probably experiencing overheating issues. One of the things that I personally recommend when using a laptop is using some sort of laptop "cooler" that uses one or two fans (powered via a USB port on the laptop) to provide active cooling to the underside of the laptop case. It also serves to keep some distance between the bottom of the laptop and any other surface you might have it resting on (such as your lap). This is what I use with my Toshiba laptop computer: http://www.newegg.com/Product/Product.a ... 6834998492
I see, after Googling your particular model of Acer laptop, that you have an AMD Phenom X4 Quad-Core N970 2.2 GHz processor. Knowing how Acer builds their laptops, I suspect you are suffering an overheating issue. Before you do anything else, get a can of compressed air and try removing any removable panels on the underside of the laptop and carefully blow out any dust that may have accumulated in your laptop. To monitor your laptop's CPU and hard drive temperatures in Windows, you might want to use Speedfan or BatteryCare.