Hello and welcome jim mate please follow this as the specs are a bit thin on the ground .
SYSTEM SPECS 7
Now before we can help we do need to know what is in your machine so please do this
System Info - See Your System Specs - Windows 7 Help Forums
or either enter the specs of your system in your forum profile the specs will appear when we click on that little box bottom left of the post screen it is for me the preferable option as it is easy. As you may appreciate it is very hard when you don’t know what one is working with for example a diesel or petrol engine.
*(pretyped to save time)
Now just as a starter have you tried an sfc and chkdsk if not please follow these and also run the other scans
SFC /SCANNOW Command - System File Checker - Windows 7 Help Forums
Disk Check - Windows 7 Help Forums < if necessary include the /f and /r in the command line as per Option2
if no change then try these
SUPERAntiSpyware | Remove Malware | Remove Spyware - AntiMalware, AntiSpyware, AntiAdware!
Malwarebytes | Malwarebytes for Windows
AdwCleaner Download
ADW download from bleeping computer delete any rubbish found with the malware scans
NB If anyone who has Kaspersky as their security they may find it will not like ADW running and to stop the nagging just temporarily disbale the Kaspersky while one runs ADW
One other thing is I see you are using Avast so please try disabling that while trying what you are.