If you're interested in any hiking whatsoever, I'd highly recommend Mt. LeConte at Smoky. I believe there's an option of hiking up to Alum Cave, which is quite manageable, or heading all the way to the top, where there's a cabin with food and water. Outstanding views no matter how far up you go.
Also, a little bit of extra driving, but Blue Ridge Parkway is top notch. Probably at its best in the fall, but I reckon still gorgeous this time of year (the trees were still mostly leaf-less when we went through.
