yes is legal
Yes.
From what i understand, HID kits are illegal unless you have a projector installed on your car so it controls the light output of the HID's. Projectors spread the light evenly and have a cut off point which don't blind on coming drivers. Don't just install the hid kit, replace your headlights with projects =)
2000 k
no
A ballast is a ballast in most cases. So yes you should be fine.
Any aftermarket addition to your headlights or taillights is considered illegal. With more and more vehicles driving off the lot with HID's coming as an option, police are less inclined to pull you over. I have had 8k's in my headlights and fog lots on my jeep for over a year with no problem. If you get pulled over, just say they came with the car when you bought it. The reason they are illegal is because aftermarket kits do not have anti-glare systems built into them because the housing was not made for HID bulbs.
HID headlamps designed, engineered, manufactured, and certified or type-approved as HID headlamps are legal everywhere. "HID kits" and "projector retrofits", where HID bulbs are installed in headlamps not originally designed to accept them, are unsafe and illegal everywhere.
Yes.
There are several ways this can go. Technically HID's and any bulb that was not retrofitted to the vehicle by the factory is illegal because it is not DOT approved. However with out a HID conversion kit I run PIAA 7,000K bulbs in a 1995 Ford Windstar LX and have never had a problem in Illinois, Indiana, Michigan, Ohio or Wisconsin.
Yes, HID lights need a ballast.
no