I'd suggest to write a quick reminder of your upcoming visit a few days ahead here, in this forum
There is a dedicated thread:
Idea: The ZRH long layover Meetup thread
We'll be able to provide you with detailed informations (like weather, if you tell us your interests give you ideas what to do, or also meet up/give you a local tour, do some activites with you&your family)
For the hotel, it really depends. If you're not bound by a chain (and it's advantages), then I'd choose something reasonably central.
Did a quick Trivago search for the 3rd October, and assuming you're a couple, here are a few suggestions. Apparently, the date is relatively expensive:
Around 100 CHF:
Hotel The Guests' House: it's reasonable 3*, easily reachable from the main station by train, quiet neighborhood - but you're quickly at the action, too. I had friends staying there before, they actually liked it. 100 CHF
The Ibis Zürich Messe is also 100 CHF, but the location is fairly remote (but not bad from/to the airport, but with a long'ish stay, I'd consider elsewhere. It's definitely higher quality than the Guests House, though)
Around 150 CHF:
Krone Unterstrass - 152 CHF, probably my pick for reasonable location+quality, convenient
Crowne Plaza Zurich - 150 CHF, also quite a good deal, easy to get by tram.
H+ Hotel Zürich - 140 CHF, new'ish, good deal, easy to get by tram
Best Western Hotel Spirgarten - nothing wrong here, but a bit less rated than those above (but slightly cheaper as well), easy to get by tram
Personally, I don't think the more expensive places are really that much better, or they're SOOOO much more expensive that it's simply not worth it. I usually suggest some of the hotels above to anyone visiting Zürich on a reasonable budget, and I've not heard them being dissappointed by them.