The smoke on startup sounds pretty normal to me if you don't smell anything funny along with it. It's more pronounced in colder climates. Condensation in the exhaust is not uncommon, and burns off after a few minutes of driving.
As for the idle, try cleaning or replacing your idle control valve. If it gets stuck or is closed, the car tends to run richer and will burn more petrol.
Last edited by Dudesky_E36; 10-22-2005 at 09:03 AM.