Windows 7 loading with blank monitor screen!

Hey all, I am using windows 7 home basic on my compaq presario cq 40 604 tx laptop. The issue is: whenever i start my laptop, it starts/load windows with blank monitor and cursor on the monitor. Now, i click alt+ctrl+del key combination so that i can access task manager. In the process tab, there is no process 'explorer.exe' that enables windows background, so i started that process manually and the windows background loads properly after that. It seems that somehow, some setting of windows gets corrupted due to which all the process that should load when windows starts are not loading automatically. Can anyone let me know the reason, why it starts happening and how can i correct it? Please be informed that till now, i have also not created any system restore point. So please advise accordingly.

My advice would be to do a 'Repair Install.
Follow Brink's tutorial here: http://www.sevenforums.com/tutorials/3413-…tall.html?ltr=R