"Only Full Albums" only exports the albums that fulfil the criteria for a full album. Turning this off includes albums which don't qualify, and also other pseudo-track collections (if you have a set of tracks by The Beatles for example, which have no album attribute, it groups these under a pseudo track-collection by The Beatles titled "Non-Album Tracks").
"Only Titled Artists" means than an artist entry is only created for artists who have albums for which they are the artist in all tracks ("titled artist"). So if an artist ONLY appears in compilations that artist won't appear as an index entry in the catalog (the compilation appears under "Various Artists"). If like me you have hundreds of obscure artists that appear ONLY on one or more compilation albums, they won't appear in the catalog index if you tick "Only Titled Artists". These are the same artists that appear under the "Other Artists" link in the Artist Cloud view. If an artist is a titled artist for one or more albums (i.e. an entry is already created for that artist in the catalog), it will still list compilations for which that artist also contributes, for completeness of that artist entry in the catalog.
WIKI PAGE TO BE COMPLETED