Laptop is slow at times and browsers freeze

Hey all, I have been having a problem lately with my dell laptop. It suddenly freezes and goes really slow. I think there might be some files corrupted or something. I have run superantispyware, and malwarebytes. Superantispyware only found cookies. Thought maybe someone could help me solve the problem so I dont have to set back to factory settings. My laptop is a dell inspiron 15. Any help would be appreciated, I am still trying to get used to windows 8.1 Here is the info

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: Intel(R) Core(TM) i3-3227U CPU @ 1.90GHz, Intel64 Family 6 Model 58 Stepping 9
Processor Count: 4
RAM: 6013 Mb
Graphics Card: Intel(R) HD Graphics 4000, -1984 Mb
Hard Drives: C: Total - 463460 MB, Free - 399321 MB;
Motherboard: Dell Inc., 033MX4
Antivirus: Windows Defender, Disabled