There should be no need to worry about the location, if at some point the data1.dat was in a system folder and deleted then it is protected by the system restore function and saved in a restore point within the System Volume Information folder.
In the System Volume Information folder the restore points are inert unless you use system restore to go back to a point that would include that file, then it would be restored. Again, it would be inert as the .cab file is an archive and has to be extracted for anything inside to possibly be active. At the point of extraction, new files are effectively created and newly created files (depending on file type) will be scanned by avast's standard shield, so nothing to worry about in that regard either.
I would suggest you look at the size of the System Volume Information folder as unchecked it can grow enormous, I have seen them as large as 1.5GB and some restore points so old as to be pretty worthless. So if your system is running fins I would suggest a bit of housekeeping in the System Volume Information folder.
Create Clean Restore Point - Clear old Restore Points.
Now you are clear of infection and your system is running fine, create a clean System Restore point:
1. Click Start, All Programs, Accessories, System tools, System Restore.
2. In the pop-up that appears fill in the radio button to Create a Restore Point
3. Click NEXT
4. Enter a useful name that you will remember if you need to find this again (Clean Restore Point)
5. Click CREATE
You now have a clean restore point, you should clear the old ones:
1. Click Start, All Programs, Accessories, System tools, Disk Clean Up
2. Click OK on the C: drive
3. Click the More Options tab
4. In the System Restore section click the Clean Up button