Windows Explorer Not Responding (White Screen)

Hi, When I try to save files from Google, Office 2013 or any program in Windows 8.1, I get a partial white screen and a "Not Responding" message on the Title Bar.

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: Intel(R) Xeon(R) CPU E3-1220 v3 @ 3.10GHz, Intel64 Family 6 Model 60 Stepping 3
Processor Count: 4
RAM: 8117 Mb
Graphics Card: NVIDIA Quadro K600, 1024 Mb
Hard Drives: C: Total - 114120 MB, Free - 69409 MB; D: Total - 953866 MB, Free - 878232 MB; L: Total - 953835 MB, Free - 868544 MB;
Motherboard: ASRock, H87 Pro4
Antivirus: AVG Internet Security 2014, Updated and Enabled