The gravitational acceleration a person experiences is derived from the mass of the body we're relating to, and the distance of the person from that body's center of gravity. On Earth's surface, this is nominally about 9.8 m/s^2, or what we call "one gravity." On Jupiter's "surface", the experienced acceleration is much greater.
However, if one could hold a position at 110,000 km from Jupiter's center of gravity, one would experience an acceleration of about one gravity, making the planetary experience, on the whole, much more comfortable. (Radiation belts aside.) If one were to build a shell around Jupiter with an outer radius of 110,000 km, one would also get a surface area of 19.6 billion square miles, or over 99 times the surface area of Earth. *Lots* of living space, and, unlike some other celestial megastructures, your atmosphere is stuck to your shell by gravity.
The question becomes, what would one want to build such a thing out of? I don't have a background in mechanical or architectural engineering, which is why I come to you folks. I imagine one would want concrete, as I picture the stresses forcing the shell to compress laterally across its surface. But how much concrete would one need? How much water (A scarce resource in space, though Jupiter happens to have a large ice moon) would be needed?
Another engineering-related line of thought I can't follow up on is the effect of tidal forces...Jupiter has several large moons. How much of an effect would they have on the shell?
Incidentally, this is part of a sci-fi world-building project I'm working on called Grokked Universe. Here's the relevant thread: http://guforum.shortcircuit.us/index.php?topic8.0