Minecraft launcher is unresponsive

Attempt to launch it as with administrator privileges. right click > run as administrator

If this doesn't work then delete your .minecraft folder. To find this press the windows + r button at the same time. This will bring up the run menu. In here type ℅appdata℅ and run it. The .minecraft folder should be at the top. Open it up and delete its contents. This will destroy your saved data ( although you can back that up). After this has been deleted reinstall minecraft and restart your computer.

To back up your saves for example simply just copy the world folder to your desktop and then add it back into your new installation when you want to access them again. DO IT NOW BISH

You should try to delete your .minecraft folder.
On windows you'd press WIN+R and type %appdata%. Now copy the saves folder in the .minecraft folder to a save place, and delete the whole .minecraft folder.
Then download the launcher again and see if it works.