Apps are not opening in Mac Google Chrome and other apps are not opening, they just bounce and then stop without giving me any error message.

I also re-downloaded Google Chrome and still not opening.

Recently I installed windows 8 via bootcamp and I had to delete lots of useless files I maybe deleted an important file by accident.

Here is a screenshot of the files that won't get deleted from my trash.(possibly important)
  

Please help me with this problem. And if it requires terminal I'm fine with it.
I'm running OS X Yosemite Version 10.10.1 MacBook Pro (15-inch, Mid 2012)
First step: don't delete "useless" files.

If the first step was not done properly, please continue to the second step.

Second step: Perform a recovery.
This will restore the OS to its original state but will leave your user data intact.