Most of the files detected are System Restore Points. Those are files kept for back-up. Unfortunately, it seems like malwares itself, were backed-up as well. May I suggest you to delete your System Restore Points first.
Clearing System Restore Points
1 Click Start, click All Programs, click Accessories, click System Tools, and then click System Restore.
2 Click to add a check mark beside Turn off System Restore on all Drives, and click Apply.
3 When you are warned that all existing Restore Points will be deleted, click Yes to continue.
All system restore points are deleted. Now you should manually create a restore point.
1 Click Start, click All Programs, click Accessories, click System Tools, and then click System Restore.
2 Click Create a Restore Point, and then click Next.
3 Name your restore point. (I use the date as well as a descriptive term such as "After Restore Point Deletion.")
Proceed performing another scan with avast.