Hermione would probably try to engage Voldemort in conversation. She might ask him questions about his motives and his plans, all the while thinking of ways to outsmart him. She wouldn't just sit there passively; she'd be constantly looking for an opportunity to use her magic against him, even if it's in a small way like creating a distraction.
She would be terrified at first, but quickly gather her wits. Hermione is very intelligent, so she would likely start observing her surroundings, looking for any possible means of escape or a way to send a signal to her friends.
Hermione might initially be shocked and afraid, but she would quickly gather her wits. She would assess Draco, trying to figure out if there was any way to sway him to her side. Given her ability to see the good in people, she might try to appeal to any sense of morality Draco has left, all while secretly planning her escape or a way to undermine Voldemort's plan of using her as a pawn against the good side.
The Gryffindor house would be in an uproar. Her friends and classmates would be desperate to do something. Neville, for example, might step up more than ever, given his own growth in courage. They would likely start by informing the teachers, like McGonagall, who would then take the matter to Dumbledore's Army.
She is likely to be defiant. Hermione has always been a strong - willed character. So she would probably not go down without a fight. She might immediately start looking for ways to escape or undermine Dolohov's plans.
In 'Hermione's Ordeal', she is initially shocked but quickly composes herself. She tries to negotiate with her kidnappers, using her wits to buy time. She also attempts to analyze their motives and weaknesses, which is very Hermione - like. She doesn't just sit there and wait to be rescued; she actively tries to find a way out of the situation.
In one possible plot, Voldemort might kidnap Hermione to use her knowledge of magic against Harry. He could try to force her to reveal secrets about Dumbledore's plans or the location of certain powerful magical artifacts. Hermione, being strong - willed, would resist and try to outwit Voldemort using her intelligence.
Hermione often shows great courage in these situations. At first, she might be scared, but she soon overcomes it. She tries to gather information about her kidnappers and their plans. If they are trying to 'adopt' her, she questions their motives and tries to find out what they really want from her. She may use her intelligence to manipulate the situation to her advantage. For instance, she could pretend to go along with their adoption idea while secretly planning her escape. She also tries to stay true to her values. If her kidnappers have a different view on things like the treatment of Muggles, she will not be afraid to speak up and defend her beliefs, even in a captive situation.
Hermione would likely be very angry at first. She is a strong - willed character and being kidnapped would go against all her principles of freedom and rights. She would probably try to reason with Ron immediately, using her logical arguments to make him see how wrong his actions are.
Sakura would probably be initially terrified. She would try to use her medical ninjutsu skills to defend herself or at least slow Itachi down. If she realizes she can't overpower him physically, she might try to talk to him, asking him why he's doing this.
Peter would probably be really confused at first. He looks up to Tony, and suddenly being kidnapped by him would be a huge shock. He might try to talk to Tony, asking him why he's doing this.
Hermione would be extremely worried and would start researching like crazy to find out where Dumbledore has taken Harry. She would probably suspect that something is not right with Dumbledore and would try to convince Ron to help her. Ron, on the other hand, would be initially shocked but then would be ready to go on a rescue mission with Hermione.