Hey,
First let me Congragulate you for having taken a decision of quitting smoking.Keep away from it now;)
As far as diet is concerened have small meals at regular interval.Walk for 45 minutes a day with average speed of 6-6.5 km/hr.Drink lot of water.Eat lots of salads.Do some weight training (3Days in a week).Practice some breathing exercises like yoga.I am sure you will start loosing extar weight.
All the best.
Uday.