I find LSR's go one of two ways. It either feels far easier than you thought it was going to be, or you start to feel like hell about halfway through and wonder why the hell you're putting yourself through this.
On the brightside tough LSR's don't mean you'll struggle on the day. I really struggled on all my LSR's for Paris this spring, but ran my second fastest marathon time come race day!
Nurse - Glad to hear you have the childcare sorted and seem to be getting back out running again.
Booktrunk - I have to admit I'm very wary of people changing their regular diet in the days prior to a marathon. That's just introducing a new risk to me.
If you can go out and do a 20 mile training run off your regular diet then the 26.2 of a marathon isn't going to take much longer. The only change I make is I eat a little bit more, but I eat the exact same food types I've eaten in training. Your long training runs should be used to get an idea of what works for you in terms of diet for the day of the race and the day(s) before.
Taper means reduction in miles, not stopping. I'd also keep the intensity of your runs up during this time too.
I do the same as KeyserSuze. In that the number of runs remain the same, but the distance drops. The reduction in distance on my midweek runs is fairly minor. It's the long run that really drops. I'll run 20 or 22 miles on September 6th depending on what I feel like. The weekend after that I'll drop my LSR to 14 miles, then the weekend after that (the one before the marathon) I'll do 10 miles as my LSR.
The week leading up to race day I tend to only very short runs to keep the legs loosened up.
Pete - I do a three week taper. I've done two weeks tapers in the past, but feel much better on the day off three weeks.
The fact is the benefit in training is over the period of the 18/16 etc weeks you've been training for, not the last two weeks of that. If anything hitting the big miles at that point is only keeping your fatigue levels high and will worsen your race day performance.
The best marathon time I've ran there was one week in that three week taper I didn't run a single step as I broke a toe.
Helga - The first rule of marathon training. Never try to play catch-up with your training plan.
Suze - I'm planning to do a 20 the first weekend in September before starting to taper, weekend of the 6/7th. That would allow allow a three week taper. I've ran off two week tapers before too and got on fine, but I certainly seem to benefit from a three week one.