If you just want to read pdf and donot want to comment in it you should use sumatra pdf. It is small in size and does support .epub besides .pdf. If you want to comment adobe reader dc or foxit pdf...

Do this in safe mode-
First download this driver-http://support.lenovo.com/in/en/downloads/ds103716
Then uninstall the elantech driver from 'uninstall a program'. This may freeze your touch pad....

you may use a 3rd party software such as detection agent from Main - Who Is On My WiFi

In router page check for something that shows 'Network status' or 'DHCP clients'

Have you installed 'Mouse and Keyboard center' or like app that is set to 'delete' contents on every click/double click?
If yes please change its setting.
Do you use Auto Hot Key?
Check in...

Open cmd (As administrator) and write
sfc /scannow
This should fix system issues.
If it fails, please post the screen shot of cmd

Boot in safemode and Try rolling back the update-
Control Panel\Programs\Programs and Features\Installed updates
Select the update with the date and uninstall.

Does win+m work?

This is happening because you have a super HD display and dr java is written in smaller resolution
You can use this method
Tell Windows to look for an external manifest file:
Press Windows Button...

Try replacing the battery and check whether it starts. Don't buy one unless this solves the problem.

Try extending the Documents partition without formatting 350mb unallocated.

Go to regedit-
HKEY_CLASSES_ROOT\*\shellex\ContextMenuHandlers
and delete those folders you donot require.
Third party app that does this-
http://www.thewindowsclub.com/downloads/CME-W7V.zip