Ouch... Ok... don't delete the files in your templates_c directory... not until you copy them into your real files. You are right in that the files in that directory are more plentiful than other directories. This is because any file (not just the ones in the templates directory) that you can edit gets cached there. This includes files located deeper into the templates directory (such as the CSS or Admin directories), etc. Fortunately, since the files are copies of your real files, you can just replace them with the files in your cache directory.