I used the Intermediate II plan for my first marathon and enjoyed the simplicity of it, adding in the odd bit of tempo running when I felt like it. Like Cookie I liked the back-to-back race pace and long runs on the Saturday/Sunday, as it gave me confidence to tackle the full distance on fresh legs, and really wasn't too taxing when you got used to it.
W.r.t. warm-ups, I'd always ease myself in to any tempo or hill running with at least a mile at either end, but include the easy running sections as part of the overall mileage. For a "race pace" run, the overall intensity isn't massively faster than an easy run, so I'd just progressively up the speed over the first mile or so, then ease into the tempo of race-pace. Maybe take splits when you get nearer the day and see how close you can get to target pace (if you have one) after the first mile.
And if you're not sure what pace to run each session, I'd say err on the side of "easy".