Do Repair Avast:
1. Avast GUI -> Settings -> Troubleshooting
2. Click on 'REPAIR APP'.
3. Follow instructions.
4. Reboot.
If Repair doesn't fix the problem, try the following:
If your Avast settings are not the default settings and you want them restored after the Clean Install, follow this before removing Avast.
https://goo.gl/TXjM7h
Clean Install of Avast:
https://goo.gl/4Ptzkf
Thanks for the help, Be Secure. The short version is it's fixed. Thanks!
Long version for those interested:
Repair App did not work. It said it may take some time, and after a while I started timing it. After 30 minutes from that point, I gave up and had to Log Off to get it to stop.
I then followed the link above and unplugged from the Internet and tried uninstalling Avast from the Control Panel. That hung the machine, too. I didn't time it but after more than 5 minutes of the uninstaller trying to stop the Avast Service, I had to manually stop it with Task Manager. The uninstaller then finished fairly quickly.
I then ran, as per instructions in the link, the Uninstall Utility. That went fine (but it was scary with the hung-ups I had).
After re-reboot I connected to the Internet and installed Avast Free. It went fairly smoothly, too. The only thing I noticed is when it ran it's first scan it seemed to 'take forever' and I had a blank window for a while.
This might be my imagination here, but on another reboot, it sure seemed to boot up faster than before. It felt snappy but I've never timed boot times.
Again, thanks for the help.