Windows Media Center Cannot Open Files

My father has windows 7 with new computer. all files and programs have ended up 'in' media center and cannot be opened. Card games, excel, word, IE, printer, etc. All icons have which used to be recognizable for the file or program now have microsoft icons. Any attempt to launch from the control panel etc are directed into the media center. Games are in 'extras' ie, exel, word, printer are in 'tasks'. NOTHING will work. If we removed media center im afraid all files and programs will disapear. he says he tried to removed it and the error message said: microsoft cannot perform this function. Ive looked at it and must admit, Im baffled. Media center has absorbed every file and progrfam on his computer