How can I edit (or even delete) these collection folers that are appearing on the interface? Even if I re-create the collections, the old useless folders still remain.
If you put your cursor above the collection name without selecting it can you use right mouse click and from menu choose delete?
On a Mac the path for the collection is to be found in the user library (hidden by default per OSX 10.7, use menu Go with option and the library will appear)
User (your name) / library / application Support / Adobe/ Bridge CS xx / Collections. Inhere are the collection names that you also can delete manually.
Windows might have a similar path but I don't that