Help Major Windows 7 Computer Problems?

Hi, I’m having major computer problems. Whenever I startup my computer windows media center continuously pops up and I can’t use any other application because every couple seconds it makes itself the dominant application. I noticed many icons have a windows logo on them and when i click on them it opens windows media center. I have managed to find out that from within windows media center i can open the game chess titans and that gives me time to open up the task manager and close the program ehshell.exe. I believe the error is related to that process because windows media center won’t continously pop up after I manage to stop that process. However, like I said before, many shortcuts like mozilla firefox, internet explorer, google chrome, titan maximum security, open up windows media center instead of doing what they’re supposed to do. In my laptop, the file ehshell.exe is located in the folder computer-os (c:)-Windows-ehome. Is it possible that this file is a virus, or is it some other problem related to this file? What can I do to fix this and thanks for any input? The file ehshell.exe is 102kb.