1. Non-class moves
If it's not a move, its still a conversation. The GM says something, likely a move. A few examples:
The fighter says "The guards are tired, right? I just duck into the bushes and get past them." I know the guards aren't really paying attention, so I say "Sure, you do it, the guards are slackers." That wouldn't be a move for anyone.
The fighter says "The guards are tired, right? I just duck into the bushes and get past them." The fighter's wearing plate and the bushes are dense, but they might still hear him. I think that the fiction demands a move. "That's probably loud enough to startle them, since you're all armored. I think you'll you'll have to take off your armor to do it without waking them."
The fighter says "The guards are tired, right? I just duck into the bushes and get past them." The fighter's wearing plate and the bushes are dense, but they might still hear him. I think that the fiction demands a move. "That's probably loud enough to startle them, since you're all armored. I think you'll you'll have to take off your armor to do it without waking them." The fighter's not willing to go unarmored, so he says "Could I put my armor in my bag and carry it through? That'd be quieter." "I think then you'd be avoiding the impending danger, sounds like Defy danger."
Broadly that shows off your three options: it's not really a move for anyone, it's a chance for you to make a (soft) move, it's Defy Danger. Defy Danger is deliberately a catch-all (especially for careful movements and stunts) so use it freely.
2. Things don't really happen passively, ever. In your example, standing guard isn't a move. The player says "I'm staying up, standing guard, while the party sleeps" and then you say "Just as the moon crests the trees, there's some rustling in the bushes. What are you doing when that happens?"
Very few moves apply on the "I spend hours doing this" level. It's a good idea to drill down if you find yourself trying to shoehorn a move into a bigger timescale. Some do cover longer periods, like Perilous Journey, of course. But you don't Discern Realities for the night like you would make a Spot check.
You also don't punish players with that, of course. Don't play it like the player's already missed clues. You cut to the first point where the character has a chance to do something interesting.
Because really that's the point. We don't really care about the hours spent waiting, we want to cut to the point where things happen. Think of it like a movie, where we'd cut from "I'll take the watch tonight" to an odd sound in the darkness.
For reference, in my example, here's how it might play out:
Player: "Rustling, eh? Maybe those orcs caught up to us. I've been sharpening my blade, but I stop and get up, real casually, like I'm just going to the bushes to relieve myself, but I'm really scanning the darkness."
Me: "Sound like discern realities, you've taken action to investigate."
Player: "Okay... uh oh, a 4. Guess maybe someone with higher Wis should have taken watch."
Me: (Oooh, a hard move! A few options jump to mind: the orcs grab him and drag him off, or maybe he find himself with a orc sword at his throat. I like the sword at the throat better, because it leads to more urgent action) "As you walk into the bushes and you eyes adjust, you almost impale yourself on a sword. It's a black orc blade, pointed at your throat. There's a gravelly voice: "Stay still, human. Cry for help and it'll be the last thing you do."
3. Risk
Michael nailed this one. I've done much the same. A cleric who decided to poke around in a refuse pile that was home to an ooze was the first character I killed in DW.
Michael's suggestions of moves are particularly good. Both are ways to still give them information, but on your terms. Offering an opportunity is also good, if you feel nice. It's still a hard move, so it's a costly opportunity: "You're poking through the bones when you accidentally trigger the spell that reanimates them. The bones start to fly together, but there's a second where you could hijack the spell. If you do it, the skeleton will be bonded to you, for better or worse, powered by a bit of your soul... what do you do?"
(For the record, if the player asked more questions about what "powered by your soul" means I'd probably play it pretty conceptually. Missing soul doesn't mean -1 to Cast a Spell, it means that when you return to town the head priest can see a difference, and worries about your soul. And who knows which infernal creature might have bargained for it, once you give it away...)