Acer laptop Win 8 running slow....

So this laptop used to run great but is now getting slow. Saw someone with a similar post where they ran farbar recovery and someone helped them out. Could I run that or HJT & post here?

Its running really slow and my antivirus keeps warning of threats when ever I open a browser.

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: Intel(R) Core(TM) i7-4702MQ CPU @ 2.20GHz, Intel64 Family 6 Model 60 Stepping 3
Processor Count: 8
RAM: 7848 Mb
Graphics Card: NVIDIA GeForce GT 750M, -1 Mb
Hard Drives: C: Total - 935180 MB, Free - 623107 MB;
Motherboard: Acer, VA70_HW
Antivirus: Windows Defender, Disabled

Thanks!
-George