Try chmodding your /opt/lampp folder into 755 with this functions in terminal.
chmod -R [permissions] [dir name]
that would be something like this:
chmod -R 755 /opt/lampp
Hey Dave look me up at Ubuntuforums I'm jingo811. I'm also learning about Apache+MySQL+PHP= thus XAMPP. Maybe if we gang up we can start a XAMPP forum folder over there so responses can be much quicker than in here.
You can read more about the security issues when mismanaging your chmodding in this thread. But then Windows always has file permission of 777 that's why things work so easy, and that's why Windows is such a virus prone OS.
Don't expect much conversations from me over there I've been so busy learning to code PHP I haven't had time to visit the forums for a week which is very unusual for my standards