Well, you seem to know a few things. One thing I will say is - don't try to change your footplant. The only reason to contemplate such a change is if you know (with no doubt) that it is causing pain/injury. If not, leave it alone.
Your 1:17 10K projects probably to a 2:50 to 3:00 half-marathon, depending on how well you train.
Gels - they're kind of like pudding but not quite so palatable. They come in little foil packets, you rip off the top and squeeze out the contents. Gels should be taken with water (not sports drink) for easier digestion. Races may or may not supply gels along the way. There will be water stations about every 2 miles. Some may also have gels and/or sports drink in addition to water. It depends on the race and is more likely in marathons than in half-marathons. Check the race web site for more info.
Water - "Drink to thirst." If you're thirsty, drink. If not, it's a toss-up (in my opinion). Don't drink just because you think you ought to. Make sure you're well hydrated all week before the race and raceday should not be an issue. The amount you can take in at water stations is usually adequate (for a half, anyway). Usually the cups will be about half full - more than that and you'll just spill it anyway. You may have to take two cups sometimes - it depends on how good the crew is about filling them. Hopefully they're paper cups. Squeeze the cup into a "V" and drink from the point. More in your mouth, less on your shirt.
Food - Eat well the day/night before, but don't stuff yourself or you'll feel it on race morning. Morning of eat lightly if at all, and at least two hours before the race. Something high carb, like a bagel, usually works well. If you eat, you want to give it time to clear your stomach before the race starts.
Training - The only caution I would give about tha Active plan is speedwork - stride/tempo/fartlek/intervals, what have you. I would recommend you avoid speedwork at this point, unless you are already very familiar with it. Introducing speedwork should be done gradually, and these circumstances are not the best time for it. For more general advice, look at Hal Higdon's Novice plans, not necessarily for the schedule but for the advice he gives before the schedule. (http://www.halhigdon.com/training/51131/Half-Marathon-Novice-1-Training-Program)
Good luck, have fun!