Totally agree with Archus. Once you lose some pounds, you'll get even more motivated!
I suggest aiming for the low end of the BMI range. Studies indicate that being on the lower end confers more health benefits.
Where did the 101 ounces come from? Is that the half-your-weight thing in water? I always just drink when I'm thirsty when I'm fasting, same as when I'm eating; I never tried to figure out the amount. But if you're a "troubled" drinker, meaning you have trouble getting down enough water, then counting is probably a good way to stay focused. :)