I've never seen anyone report that particular weirdness (not being able to launch applications) before.
Please post your specs: CPU, RAM, video card.
Also, what version is your graphics driver? I'm looking for the major number, so if it's Nvidia it's xxx.xx, AMD/ATI it's xx.xx.
Also, I'd like you to run the System File Checker, a built-in Windows utility that checks the integrity of system files and replaces any corruption it finds. To do this, open a command prompt as administrator, and then type this command:
sfc /scannow
Is there any reason you're not using Windows 8.1? I'm not specifically suggesting that upgrading to 8.1 will fix the issue, but you're actually running an out-of-date version of Windows. It's a free update. However, put that aside for now.
Put it better than I did. Another thing that you could do is update your video drivers.