Lots of questions in one post, maq.

And to be honest, they really don't have much to do with the thread topic; you're probably better off asking such questions in the 'newbie thread' in the General Discussions forum. But here we go anyway ---
- I'd guess the preferred gov would be democracy, but it has no effect on your game whether you're in it or not. [Other civs' attitudes do depend to some extent on which government you're in, but that has nothing to do with your own preferred gov.] So choose whichever government is right for what you're doing.
- I build roads first in most situations for two reasons: 1) if a barbarian shows up, the worker has a better chance to be able to get well away if the road's built first, 2) later on in the game, once the road's built, other workers can join in to complete the mine/road without wasting movement.
- I have no idea what the most logical victory will be with this game. The consensus does seem to be that space race is usually easiest, for several reasons: 1) You don't have to take as much care with your reputation as with diplomatic, 2) the human advantage vs. the AI tends to increase as the game goes on, so later victories can often be obtained even with relatively weak starts, 3) Often, little to no offensive warfare is required.
- I will probably use that exact research order. Mileage will surely differ, though.
- 'Never mind' never hurts. (Nor does opening the diplomacy just to check out how much money a civ has, or some such, for that matter.) But frequent trade (at least once every 20 turns) does help attitudes.
Hope that helps,
Renata