All Applications Open "Open With" Windows 7?

computer, as I am not familiar with Windows 7. When he attempts to open an application (any application) it opens an "Open With" window with only IE 8 and Word Pad as the only recommended programs.He's figured a PITA work around by right clicking the application icon and selecting "Run as Administrator" and then it opens after clicking through the security window. My initial thought was that his account was somehow changed from an Administrator account to a standard account, but that proved incorrect.I'm thinking it's some virus or malware that's causing this, but I see no other apparent signs of infection (i.e. degradation in performance) and he is protected by a current Antivirus (Eset), so I'm also thinking there may be some corruption of his system files, but like I said, I'm a novice where Windows 7 is concerned.