35 years in CT and I don't recall ever seeing nice colors at Halloween... ever. Since you wrote that you are definitely planning for the last week of October and your dates are not flexible, I would not expect to see nice colors at that time. It would be a strange thing. And the further north you go, from Newport into upper New England, the earlier they'll have fallen, usually totally brown and down way before Halloween.
So with your dates, your options may include:
1. Continue with a pre-holidays New England vacation - enjoy other activities and sightseeing but don't plan on Autumn colors. Boston & New York City offer much to do in urban settings where the leafless trees may matter less.
2. Travel southward for that week to central Virginia's mountains, about 6-9 hours from Newport, I'd guess. The drive along the Blue Ridge Parkway is very scenic and beautiful. Check out Charlottesville, Luray Caverns and other Shenandoah sights. Depending on the weather this summer/early fall, you may have a better chance of seeing some color in the valley at the end of October.
3. Travel further down toward Great Smoky Mountain National Park in Tennessee or North Carolina - perhaps 14-18 hours but worth it to me. Besides lovely drives along the Blue Ridge Parkway, the 3rd and 4th weeks of October are typically prime color weeks for the Blue Ridge Mountains in NC - this year we even had nice color in spots into mid-November, though it was such an odd year. The Asheville, NC area and the Gatlinburg, TN area are both chock full of fun things to do and it's a very popular time to visit either place - really pretty.