There are three levels of minimum wage, and the rates from 1st October 2007 are:
£5.52 per hour for workers aged 22 years and older
A development rate of £4.60 per hour for workers aged 18-21 inclusive
£3.40 per hour for all workers under the age of 18, who are no longer of compulsory school age.
Sorry I'm late on this mate, a suit is a must imo. Polish your shoes, wear a belt, cut your nails, smarten yourself up to the max.
When you enter the room smile, say hello, shake hands, make eye contact when doing so and smile again. Sit down if there is a seat. Keep your body language open, take your time and relax. You don't have to answer every question and don't be afraid to ask to come back to that one.
Most interviews are competancy based these days - so have a few eg's of common ones - team player, solving a problem, dealing with confrontation, etc etc.