3) will for present habits:
There is no question that the verb (or verbs; there may be several) will is one of the very trickiest ones in the English language for foreigners ever to master. The deontic senses are seldom intuitive to a non-native speaker. I strongly advise you to carefully study the OED’s entry for this word’s incredibly many subtle uses.
In this case, your two examples are not of the same thing at all, and you have mischaracterized them. The first uses will to express habitual action; it does not indicate a simple future situation. This is the OED’s sense 8 for this verb:
8. Expressing natural disposition to do something, and hence habitual action: Has the habit, or ‘a way’, of ––ing; is addicted or accustomed to ––ing; habitually does; sometimes connoting ‘may be expected to’
This is related to sense 15, which is still not a simple future, albeit perhaps closer to that:
15. As auxiliary of future expressing a contingent event, or a result to be expected, in a supposed case or under particular conditions (with the condition expressed by a conditional, temporal, or imper. clause, or otherwise implied).
Your second example, the one about the car, is completely different. This corresponds to OED sense 12:
12. With negative, expressing the contrary of senses (def#6), (def#7), (def#10), (def#11): thus commonly = refuse or decline to; emph. insist on or persist in not --ing. Also fig. of a thing. (See also (def#9), (def#13).)
Here, your car is persisting in not starting. It is the figurative sense at the end extending to things, as though they had the will to refuse. The referenced senses 9 and 13 are respectively:
9. Expressing potentiality, capacity, or sufficiency: Can, may, is able to, is capable of --ing; is (large) enough or sufficient to.
15. As auxiliary of future expressing a contingent event, or a result to be expected, in a supposed case or under particular conditions (with the condition expressed by a conditional, temporal, or imper. clause, or otherwise implied).
As I said, will is quite complex. Please study standard reference works regarding its use.
The way these prepositions are used in these examples has nothing to do with the fact that "categorize" occurs in the sentence.
1: "in" is part of the adverbial phrase "in many different ways". This could be apt for a multitude of main verbs. "He painted in many different ways." "they walked in many different ways".
There's nothing special here with regard to using "in" with "categorize", even though they are collocated.
2: this is a shorter adverbial phrase "as conservative". If I inderstand the terminology, "as" links a stative verb with its predicate adjective. This usage fits a narrower range of main verbs, such as "viewed", "seen", "tagged", "understood". (See http://www.google.com/search?q=define+as&ie=UTF-8&oe=UTF-8&hl=en , meaning 1 for prepositional use of "as")
3: "in this field guide" is, as in #1, an adverbial phrase that could be applied to many verbs. "There are many pictures in this field guide." "John Muir was quoted in this field guide." As in #1, there's nothing instructive here with regard to using "in" with "categorize", but in this example they are not collocated; "in" is NOT being used WITH "categorized".
But what you should have noticed, and bolded, in this example, is by—this is the preposition associated with "categorized". In this example, "by" is used in the third bulleted meaning under the #3 sense for the Preposition ("parameter") HERE http://www.google.com/search?q=define+as&ie=UTF-8&oe=UTF-8&hl=en&#hl=en&q=define+by
A few verbs that collocate with "by" in this sense (I'm sure there must be more):
In such cases "by" can be understood as rougly equivalent to "according to".
Best Answer
Contrary to what you seem to think, wouldn't and won't are almost never interchangeable.
The simple negative won't is used for future negative actions or for refusals.
The negative wouldn't is used for counterfactual statements, and for future statements embedded in a past-tense narrative.
In every case here, replacing won't with wouldn't results in something either ungrammatical, or it changes the meaning of the sentence.
Edit: An additional requirement for will/would is tense concord, which means that subordinate verbs in a complex or compound sentence must agree in tense with the main verbs. This applies to the two halves of an if/then construction, as well as to verbs in relative clauses. For this purpose, will is considered to be present tense, and would is past tense. So you see things like:
He would be dead if he went to the store.
He says he will open the envelope.
In this case, the distinction between will/would doesn't carry any semantic weight, but is required by English grammar. Swapping will and would in any of the preceding sentences results in an ungrammatical utterance.