One habit of Windows is to create the recycled folder, mark it as system folder and prevent you from deleting it. Should not be a problem though, as this folder does not use any space. (Unless something went wrong)
The FOUND.000 folder however, is the result of the automated scandisk (mentioned before). There it creates files, which will contain data junk of possibly defective areas of the storage card / hard disk.
Unless you have lost any significant data due to a problem with the file system, and you have every file you need in place or backed up, you can savely delete this folder and its content, you will not need them anymore. I hope I explained that understandable