Laptop lag when I play videos , use office ,play games

Hello
I have laptop HP PROBOOK 4530S since 2011 and worked very well but in november 2013 my laptop start lagging , in the first the lag is limited on videos , but after I suffer the lag in games ( also old games ) , microsoft office , when I use the browsers etc.. , there is my specifications




I tried this solutions
- INSTALL the news drivers , i try install the old versions of drivers ( videos , audio , wifi , all drivers )
- Scan my computer with KIS , and also anti malware , but no change
- I defrag my hard drive
- I use VLC since 2011 and I uptade him but is it the first media player I try the others media players , like MPC-HC , in the first time the video runs very well , but the second time the lag appears , I remove mpc-hc , and try CCCP or KLITE , also the same scenario , the first time , the video works very well but the second etc.. the lag appears , I try also KMPLAYER , the same problem ,I try the change codec or disable/enable hardware acceleration but the lag persist ,
- I tried to format my laptop , when i format him , the fisrt time when I play video , the video plays very good without lag , but the second , the third time ..... the lag appears


Thank's and sorry for my bad english , I wait your help please :)

Yes is checked but I the lag persist