As it almost always is with exercise, what works best for you is an individual thing.
Looking back in my workout log I see that I used the Gym Style workouts during training for my last marathon. I didn't heavy up too much on the leg workout.
Sara/Imafitnessfreak uses whole body workouts only though. She's got a completey different body type than I do and builds muscle much easier.
I think the best thing you can do to shave minutes off your time (or in Cathy's case to have an enjoyable first marathon)is to run as many miles as you can tolerate and making sure you keep your long runs at a low intensity. A great book that Sarah shared with me is "Training For Endurance" by Dr. Philip Maffetone.
To avoid the impact of running I used my elliptical in place of running about twice a week.
I also made sure that I stretched thouroughly after every single workout. I used the first segment on Cathe's Stretch Max because it seemed to get my legs the best.
Another big thing is to work on the mental aspect as much as you do the physical. A great book I would recommend for that is "The Non-Runner's Marathon Trainer" by Davit A Whitsett, Forrest A. Dolgener and Tanjala Mabon Kole. It's relevant no matter how many marathons you've run. While you might run those last 6 miles faster than previous marathons, it still hurts!
Hope this helps somewhat! Good luck and have fun!!!
ETA: One more thing that I would suggest is to take ice baths after runs, especially the long run. And to make sure you get a recovery protein shake/meal, whatever you prefer, as soon as possible after you run. Recovering from your runs is also a huge aspect in staying healthy through training.