It seems that all Backburner is is a service. Here is what I have found and we can see if it will help. You may be able to just delete the folder after that and run a Utility like Tuneup Utilities to clean the paths out of the registry... but that's getting dirty, so attempt at your own risk. This will at least remove the service.
How do I install backburner Manager and Server as services?
Note: you must have administrator rights.
Open a command prompt (Start > Programs > Accessories > Command Prompt) and type the following:
managersvc -i [Enter] to install
managersvc -r [Enter] to remove
serversvc -i [Enter] to install
serversvc -r [Enter] to remove