High CPU usage Windows 7?

normally it happens when you have lots of programs installed on your pc(usually the one that execute at startup - the ones that appear on the taskbar.) so try uninstalling some of the programs that you don't actually need. the second thing is your pc may need defragmenting. it slows the computer to a considerable amount. run disk defragmentor. the third thing you can do is check your registry for errors by using some programs like registry first aid. hope it helps!