The green oval indicates the number of files you currently are sharing.

If you did not ask Limewire to scan for mediafiles when you installed, then the only folder shared is the Shared folder which Limewire creates and a folder in preferences that only has to do with people downloading Limewire itself. All files that you download go into the Shared folder.

You can add or remove folder by going to Tools-->Options-->Sharing or altenatively going to your library and pressing shared files.