Ok, here's the goods. I've attached the Avast boot-scan log (it's empty, essentially, but there for completeness' sake), two Malwarebytes logs, and the HijackThis log. I'm hoping we've made some real progress here. Avastfan, what next?
David, I suppose I'm happy CCleaner's registry cleaner isn't all that robust, as I certainly lack that working knowledge you mentioned. It did get rid of 1103 of those shallow issues it does address.
A question about the startup menu manager: I have a number of programs unchecked in msconfig that I did not uncheck myself. How can I know what is needed and what is not? Is it safe to use CCleaner to remove unchecked entries if I'm sure the program isn't needed or that I simply don't want it to run on startup?
I mentioned an issue I had with Avast. I ran the setup, and it downloaded the program. On first run, it performed a memory scan and warned of a hidden service named "buoraeym.sys." It asked if I wanted to delete or ignore this service, and suggested "ignore." I clicked ignore, and up popped a warning that there was a virus running in memory. It asked me if I wanted to perform a boot-scan, I clicked yes, and the system froze. I wound up doing a hard restart, and the boot-scan started. I had trouble with freezes on restarts, as Avast and TM were fighting with one another, and was eventually able to stop the apps as they were loading, boot fully, and uninstall Avast. Hence:
I don't know if the buoraeym.sys service is a problem, or if it has been solved, and
I don't know if Avast was up to date when it ran the boot-scan.
It has been stated elsewhere in the forum that Avast fails to identify these particular issues. Do you suggest mucking abot with it again, or leave it for now?