20 hours really isn't a whole lot of time to go and see Manchester, and the local NH
If you're looking for a good restaurants, a really awesome (but pricey) italian restaurant is Piccola's, it's on the right, just north of Granite Street, on Elm Street (the main downtown street). Or if you want something fast, Bob Nadeau's Subs has some of the best subs and sandwiches (especially the streak&cheese).
As for entertainment, there really isn't much around the airport. The main shopping section is near by on South Willow Street. There's a few good bars in the downtown area, but with only 20hrs, I doubt that's really an option.
And the UNH Men's Hockey will be going against UMaine at 7pm at the Civic Center, downtown.
Your men have to follow your orders. They don't have to go to your funeral.