How to hide and open folder in windows 7:
      This is pretty easy. I've verified this in my own computer several times,i swear it doesn't cause any problem to the system as well as the data content in that folder.

       Here's the way-Right click the folder you want to hide, go to properties>general>then in the bottom part, you'l find hidden option,tick that option then click apply  . Then confirmed attribute changes will be prompted, select apply changes to this folder,subfolders and files option. After that click Ok .

        To open that folder again, go to organise(located on the leftmost part of your menu bar)>folder and search option>folder option will be prompted,go to view bar and then select show hidden files and folders under advanced settings>then apply>OK