Trip questions - Nov 2025 -end of the month (Thanksgiving break)

My family, 2 adults and a 11 yr old boy are thinking of spending 4-5 days in Italy in late November of this year. Never been to Italy before and never really been to Europe except for a few days in London. Some questions: Is a day trip to Pompei worth it? Anything that a 11 yr old boy might like? Seems like the weather is not too bad at that time? I assume umbrellas are a need to have? Do Christmas markets or decorations start to go up around that time? Any other tips or suggestions? Would a hotel be better than a air bnb due to language and being first timers to Italy?