Well, I go to Shenandoah usually 2-3 times a month. Is there anything specific you're interested in? There are so many photo opportunities, waterfalls, mountain streams, cemeteries, interesting rock formations, old ruins, wildlife, flowers (even this time of year there are still some flowers left).
How much hiking are you willing to do? Most of what I find interesting requires a bit of hiking, although you can certainly burn a lot of film and never go more than 50 yards off of Skyline Drive.