I did run aswclear.exe ( version 1.0.0.1 ) in Safe mode
Selected Avast 6
Showed that files removed
Shut down Windows

Rebooted to normal desktop

Ran setup_av_free.exe ( version 6.0.1203.0 )

5 minutes later I got the BSOD shown in http://i.imgur.com/rRL1W.jpg

My only thought was that since I have been using Avast Pro since at least version 4, perhaps there are remnants of previous installations making life difficult for me now, so …

Rebooted back into Safe mode
Selected Avast 6 Free/Pro
Showed that files removed
Shut down Windows

Rebooted back into Safe mode
Selected Avast 4 Free/Pro
Showed that files removed
Shut down Windows

Rebooted back into Safe mode
Selected Avast 5 Free/Pro
Showed that files removed
Shut down Windows

Rebooted back into Safe mode
Selected Avast 32
Showed that files removed
Shut down Windows

Rebooted to normal desktop

Ran setup_av_free.exe ( version 6.0.1203.0 )

So far so good, though while typing this an Avast “Suspicious Files Found” window popped up

Suspicious files have been detected ( using a heuristic method). This may be a sign of malware infection. Please allow the files to be submitted to our virus lab for analysis. Further information File name C:/Documents and Settings\RSAS\...\sessionstore-103.js

with the Ignore / Delete options in the Actions To Take box available

I am leaving it open until I hear back from you about your advice regarding Ignore/Delete

So the good news is that I have been able to type this post without seeing a BSOD and possibly may have found an issue ( the Suspicious File Found window popped up about the same time that the BSOD usually showed up )

Thanks again for your time and advice.