-personal liberty - I think in some ways they'd be happy, in others not. In reality we enjoy a high standard of living, and anyone who wants to get ahead and is willing to work hard can do so. OTOH we have the increasingly intrusive government which WE ALLOW to intrude into our lives.
- technology - I think they'd be frankly amazed, but would immediately see the benefit of car vs horse, plane vs wagon. I'm not sure they'd see the improvement of muzzle-loader over M16, perhaps if they came back when we still had the Garand though.... Seriously, I'd expect them to embrace the technology, at least as much of it as they could understand.
- the federal government - I think what would bother them most is that the government has, in effect, taken the place of the church in our society. It used to be if you were hurt and couldn't work people from the church would give VOLUNTARILY to help you out, and the vehicle for that giving was usually the church. Now when someone can't work they look for the government to provide money that it took INVOLUNTARILY from your neighbors.
- foreign policy - I think they'd be amazed at where our foreign policy is pointed, and at what nations are non-entities. France was one of the strongest nations in the world back then. Japan was a non-issue then.
I think what would bother them most overall is that so few people take an interest in the government. Even when they do they do so now in terms of "what is BEST for me overall" but "what can I get out of this right now". In an high-school history class we called this "enlightened self-interest".
I DON'T think they'd say it was time to break out the rifles and overthrow the government. If you read the Declaration of Independence you find that they did everything they could to address the problems with England by peaceful means. We've allowed our rights to be eroded and we haven't even started the process of correcting it yet. I do think they'd tell us to get off our fat, complacent butts and get involved, turn this nation back into something resembling the one they handed over to us. Only if the government refused to respond to the mandates of the people would they consider revolution.