jsburbidge has a nice extended examination of issues with the 2014 Hugo awards. The first part deals with The Wheel of Time. Is it a novel? Or can it count as one?
If we view “novel” as a size description, then there’s a sequence Short Story, Novelette, Novella, Novel, much as books used to go up Duodecimo, Octavo, Quarto, Folio. Just as the sequence of book sizes (which were based on how many times a sheet was folded in the final volume) could be extended upwards (Elephant Folio), it might seem reasonable to extend the size-of-story upwards to include something which is not a series but is too big to be a novel. Giga-novel, maybe, or novelissimus. You’d have to find an appropriate size boundary for it, bearing in mind that War and Peace is by convention a novel and is 1296 pages long in a current translation, so the limit needs to be well over, say, 1500 pages.
However, that’s not really what’s usually meant when dividing up types of work. “Novella” and “novelette” are at best publishing categories (and since they aren’t really used as anything other than a way to talk about really long stories published, usually alongside shorter stories, in an anthology, they aren’t even that (although e-books may be changing the landscape here). Also, if War and Peace is a novel, so is (by ordinary understanding) Heart of Darkness, which is 80 pages long (the Dover version), which means that there’s a factor of 15 or so in terms of the allowable range for novels, and no obvious reason not to extend that ceiling.
We usually distinguish a novel from a collection of related short stories by one criterion only: unity of plot. That doesn’t mean that there may not be subplots, but that there is one dominant story arc, that it is announced early on, and that the novel ends at the conclusion of that arc. That’s why The Man Who Was Thursday is a novel (although its structure is episodic and its ending somewhat arbitrary) and The Poet and The Lunatics a collection of tightly related short stories with a gradually emergent story arc.
Normally, the next step up from a novel is a series of interconnected novels. These may be tightly connected (Stephenson’s Baroque Cycle probably sits at an extreme here — it’s almost a novel in three parts, but not quite (it also harks back to the mediaeval romance’s technique of entrelacement)) or very loosely connected (the individual novels in La Comédie Humaine, or in the Dance to the Music of Time).
Most tightly-connected series fall into two categories. Either they involve stand-alone volumes (Inspector Alleyn, James Bond, Dominic Flandry) even though there may be some continuity and development between volumes, or they are volumes which have the shape of novels and initially look like the first kind of series but gradually accumulate a momentum towards a larger-scale resolution of a broader story arc (Toby Daye, Harry Dresden, Miles Vorkosigan, The Malazan Book of the Fallen). In either case, it’s quite clear that the components are themselves novels: you can pick up, say, One Salt Sea or Iorich and, with a bit of careful incluing, enjoy the volume as a work in itself. The characters’ backgrounds may need some filling in, but the action is a single action.
The second part, regarding the reading of authors who one doesn’t like, is also good.