Very Slow

My new Dell Inspiron 7779 with the following specs is super slow. It takes almost 2–3 seconds to open windows explorer and 10 seconds to open Skype. When I installed Adobe Acrobat Reader, my PC went not responding for about 2 minutes. Disk often goes 100% in Task Manager after I open a program...

Hello, I bought a new laptop 2 months ago. Acer Aspire V17 Nitro Black Edition. It comes with 16GB ram, 256GB SSD, i7 4720. Everything was fine. But in the last days (maybe 1-2 weeks? not sure) it is very slow. I can still open multiple things such as firefox, a video game, chrome, skype, 2-3...