First of all let me answer about Desktop.ini file ,where .ini stands for initialization file which stores information about folder layout structure.
They can be deleted but will be generated automatically and are not advised to delete them.
Also we cannot stop auto-generation of these files as they are important for Operating System.
Next , CAFADEBUG.log - CAudioFilterAgent Debug Log file may be generated by some software that you have installed.You can find outputs from drivers in that log file.So if these files are causing harm uninstall the related software else just leave them.
If the files are causing you damage,kindly use an anti-virus program and clean rootkits.