Log in screen show but start up screen does not turn on

Hello,

Please help me!! I log in to my compaq laptop. The log in screen shows but not the start screen. It's completely blank! I think I accidentally stop a system process in task manager that made it like that. I can use the task manager and can use the browser if I open it with the task manager. The following are the only processes left:
Csrss.exe , dwm.exe , rundll32.exe , svchost.exe , taskhost.exe ,taskmgr.exe ,
Winlogon.exe

Please tell me what other syatem files should be running and how to get them back!! Also my sceen too..