Can one of the moderators please move this thread to the Virus / Malware section. Thank you.
pbmac => The reason for the scan stalling is that you have a possible ZeroAccess infection. We will try and remove what we can with this script and then check to see what else we need to do.
FIRST >>>>Please go to
START (Windows Orb) >> Control Panel >> Uninstall a Program or
Programs and Features and remove the following (if listed):
Coupon Printer for Windows
QuickTime 7
Yahoo! ToolbarTo do so, left clicking on the name once and then click
Uninstall/Change at the bar above the list window.
Follow the prompts of the uninstaller BUT please read carefully any questions it asks before answering; some uninstallers will try and deceive you into keeping the software.
SECOND >>>>
Fix with Farbar Recovery Scan Tool
This fix was created for this user for use on that particular machine. 
Running it on another one may cause damage and render the system unstable. 
Download attached
fixlist.txt file (located at the bottom of this post) and save it to the Desktop:
Both files,
FRST and
fixlist.txt have to be in the same location or the fix will not work!
- Right-click on
icon and select
Run as Administrator to start the tool.
(XP users click run after receipt of Windows Security Warning - Open File). - Press the Fix button just once and wait.
- If for some reason the tool needs a restart, please make sure you let the system restart normally. After that let the tool complete its run.
- When finished FRST will generate a log on the Desktop, called Fixlog.txt.
Please attach it to your reply.
LAST >>>>If you still have a Addition.txt log file on your desktop, please delete it now.
Start
FRST64 that is on your
Desktop by double clicking and allowing the software to run when the User Access Control asks (if it does).
The tool will start to run.
When the tool opens click
Yes to disclaimer. (if it does)
Select Additional.txt in the Optional Scans section of FRST64.
Press
Scan button.
It will make two logs (
FRST.txt and Addition.txt) on your Desktop. Please attach the logs in your reply back.