PC Randomly Freezing while inactive or upon waking up

Greetings! I am new to the forum and have been having some issues with my desktop pc. Recently I was hit with a smarthdd infection, which has been successfully removed. However, (whether related to it or not ?) after having this infection the pc has been randomly "not responding". It may go for 24+ hours and not freeze up at all and I think it's fixed, but then it does it again. It usually happens more over a longer period of inactivity, but not always.

If I leave the pc alone, the screen saver comes on and does it's thing. But sometimes when I come back, move the mouse, click on an icon and I get that little blue circle spinning (windows "not responding"). Then mouse and keyboard commands are non responsive - the mouse does move around the screen with no problem. I have to hold the power button down to shut off, upon restart the pc runs absolutely fine, from what I can see.

When it freezes, sometimes the taskbar (usually hidden) will pop up, other times no. I have a desktop gadget clock installed and have seen when it has frozen, which is prior to when I have attempted to wake up the pc, not AT the time of wake up. I haven't had any issues of it freezing while using the pc (working offline, browsing, music, video etc). The machine is working very well, other than for this random exception.

I have played with power settings - thinking that it may have to do with the machine sleeping and not waking up, but even if I have it set to "never sleep", it still freezes.

This seems to be a common issue but very difficult for a "non expert" to diagnose/navigate on my own. Any help would be greatly appreciated.

Thanks!

Just to be sure run malwarebytes

Please download the free version of Malwarebytes.
Update it immediately.
Do a full system scan
Let us know the results at the end.

Malwarebytes : Download free malware, virus and spyware tools to get your computer back in shape!


Then if all clear

Please provide us with your Event Viewer administrative logs by following these steps:


Click Start Menu
Type eventvwr into Search programs and files (do not hit enter)
Right click eventvwr.exe and click Run as administrator
Expand Custom Views
Click Administrative Events
Right click Administrative Events
Save all Events in Custom View As...
Save them in a folder where you will remember which folder and save as Errors.evtx
Go to where you saved Errors.evtx
Right click Errors.evtx -> send to -> compressed (zipped) folder
Upload the .zip file here.

Thanks so much for your reply!
Sorry, it's been one of those days. I just got home to to see Microsoft Security Essentials had caught several attempted infections just a short while ago today! My nephew was trying to view some files on an infected backup disc (coincidentally he's the same one who blessed me with the smarthdd infection). The disc has been destroyed and he's been told!!

I have been running Malwarebytes for many years. In the past week (through the removal of smarthdd and being paranoid about other malware maybe being on my pc) I've done several scans, nothing malware has shown up at all. I am currently running another full scan, which usually takes a few hours. I can upload the log when it is done, if you would like to review that.

I have attached the event viewer zip. It appears shows lots of errors, hopefully it will help with a solution.
Thanks again!

Attachment 208018

Problem Devices:

Code:

Atheros 802.11 a/b/g/n Dualband Wireless Network Module	PCI\VEN_168C&DEV_002A&SUBSYS_1000168C&REV_01\4&1AFCC52E&0&00E1	This device is disabled.

The above was probably intentional, and if so, it is nothing to worry about.

Code:

Event[1273]:
  Log Name: Application
  Source: Microsoft-Windows-Search
  Date: 2012-04-16T09:06:45.000
  Event ID: 7010
  Task: Gatherer
  Level: Error
  Opcode: N/A
  Keyword: Classic
  User: N/A
  User Name: N/A
  Computer: Andy-HP
  Description: 
The index cannot be initialized.

Details:
	The content index catalog is corrupt.  (HRESULT : 0xc0041801) (0xc0041801)

Rebuild your search index: Index - Rebuild


Also, given that the index was corrupt, check for data corruption and disk errors.

• If you are overclocking any hardware, please stop.
  
  
• Run Disk Check with both boxes checked for all HDDs and with Automatically fix file system errors checked for all SSDs. Post back your logs for the checks after finding them using Check Disk (chkdsk) - Read Event Viewer Log.
  For any drives that do not give the message:
  Windows has checked the file system and found no problems
  run disk check again as above. In other words, if it says:
  Windows has made corrections to the file system
  after running the disk check, run the disk check again.
  
  
• Run SFC /SCANNOW Command - System File Checker up to three times to fix all errors with a restart in between each. Post back if it continues to show errors after a fourth run or if the first run comes back with no integrity violations.