Issue with mouse/touch pad, Dell Inspiron 15/3000 series

I hope someone can assist.   I purchased this Dell in July of last year, within 24 hours I had to return to the Geek Squad to unlock the system for me and help me bypass the password step ... I have had issues since day one with some of the keys not responding at all upon touch or the other end of the spectrum  constantly repeating when touched .it has done it approximately every 5 words in this post already...... again returned to Geek Squad so they could  'decrease touch'  on keys --- ?not sure if thats the case or not but whatever they did slowed the process, still did not stop it.   NOW, no matter what I am doing - say I am reading a news article, when I move my mouse to the side to continue reading, it opens everything it touches or crosses ...  I have one thing open .. now have 6 or 7 pages of stuff open or pictures opening on my screen.......  annoying and I am unsure how to lower the "touch" or "sensitivity" of the touch pad or mouse --- I would think it should not open anything unless I select it by left CLICKING on the mouse  not just rolling over it     thank you for anything you can provide me ....