They look like leftovers of some malware/spyware that was removed from your system, probably by your antivirus/antispyware application.
Since you say you're a pretty savvy user, I would recommend removing these RunDLL errors by modifying registry.
Open Registry Editor, scroll to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run and see if you can find any startup commands related to these dlls. If so, delete them.
If they're hidden somewhere else use this tool to find a remove them. Autoruns for Windows
If you're still having this problem, try creating dummy files with these names and extensions in that location and see what happens.