I would suggest you to go for Udaipur trip as the weather is pleasant and currently all lakes are full. you can book a lake view resort and hotel and there are many places to visit in to cover in 2-3 days trip.
I think you can find answers yourself. You need ask these questions in sequence from yourself and to your family. 1. why are going on vacation?
2. ask interest of your kids like wild adventure, full of activities or lavish trip.
3. get voting done with in your family members. I am sure you will able finalize the destination.