To stop the Tools from automatically opening every time you open a PDF, this solution worked for me on both my desktop PC and laptop. This is the solution:
Go to C:\Program Files (x86)\Adobe\Reader 11.0\Reader\Services
Delete these 2 files: DEXShare.spi and DEXEchoSign.spi
Yes, you will still see the word "TOOLS" at the top but at least your PDFs will open in full screen and you won't have to click "Tools" to hide that stupid sidebar every time you open a PDF.