Google how to fix the administration part (you probably have to do cmd things but don't take my word for it).
I did that once and it took me 15-20 mins to fix it.
When you ARE able to mess with it again, move the folder to a different folder (I move mine to a game folder you can also just make one on your desktop), do NOT open the zipped folder, you don't have to select the files one by one, just simply right click and extract all. It probably thought you were trying to open it while it was in the zipped folder. You don't have to open to folder to extract. You just click it once to select, and right click. It'll give you a list of options and it should say around the top: extract here. It'll just make another folder with all the files in it.