well I made a circle of the state once, I don't think it took to long.
enfield to the casinos is cutting across the state, from lime rock to the casinos is some great back country roads, very fun to drive if not triaffic and Rt 7 always has some sort of traffic, 395 caps the eastern part of the state and goes right past the casinos
as for which one is better I have only been in Mohegan Sun, there are two completely seperate parts with a mall setup in the center, many places to eat, and if you don't gamble just walk around and look, there is the sky and earth casino, the earth casino is the older one and has four entrances themed with the seasons, might be different now, the sky casino is open and bright, it has the mountain that you see when the person climbs in in the comercial
as for that corner of the state there is mystic also and that is also a nice area, also you can travel up along the CT river, Gelet castle is a nice area and has some trails
for the eastern part of the state, you could go to Greenwick and westport and look in aw of the houses, see the WWE headquarters, head up rt 7 and go antiquing, The Mark Twain house is in Hartford, got the Pike and the Gold Club in Berlin and Hartford
and of course there are many nice area along the shore