Hi, There are a lot of places but it depends on your budget, visa statue and travel expectation plus are you travelling with kids or just adults? Not knowing the answer to the questions above, I can still recommend you Tanzania. You can take a week or 5 days Safari and just go wild into the wild, kids and adults will love this equally maybe kids a little bit more. Then you can go to Zanzibar to enjoy amazing islands and a relaxed gorgeous vacation. It s still hot there in October so you can go swimming. If Tanzania is too offbeat for you then Turkey is a great choice, north of Turkey where the nature will take the stress out of your system in amazing way and you can still enjoy couple hectic days in Istanbul Mexico, Colombia, some parts of Italy are also to be considered.
In Himachal You can go to 1)Trithan Valley 2)Parvati Valley 3)Manali 4) Shimla 5)Macleodganj 6)Spiti valley. In Uttrakhand you can go for Nainital,Rishikesh,Mussourie.Out of these best and Less explored is Trithan valley;For that You Have to go to AUT from Chandigarh.For the Desert Go to jaiselmar. But Due to flood problem;HP and Uttrakhand are out of options until the news come.You can go to North Sikkim;it is untouched heaven on earth.Darjelling is not as good as much it is hyped.
For family tour you can visit
Delhi-Haridwar-Rishikesh-Mussouri-Auli (10 days)
Delhi-Dharamshala-Mcleodganj-Kasol (10 days)
Delhi-Simla-Manali (10 days)
Andaman (10-11 days)
Gokarna is the best place where you will get beaches and trekking, the serene ambience and western music, hippie culture exploration and cheap stays. there are 5 beaches, and the more you trekk far the peaceful and cheaper it will be
If you are considering out of india, You can do Cambodia and Vietnam . Weather is very good from Oct to Feb. Pls read my blog . I did a solo trip to Cambodia last year