Uncle Sam's is alright - but not for the food. I've had the french fries and Philly Cheese steak and was unimpressed by both. Not terrible food, but just really average. Some of the food is a bit expensive for what it is.
The happy hour goes from 3-7pm and 9 to close. One dollar domestic drafts and 1.25 for premium. They also have a happy hour menu, too. I'd recommend sitting at the bar for the best service.