The lane on the far right is for EazyPass - a sign-up service where you get a small box to attach to your windscreen which scans each time you pass through, adds to your account and charges your credit card monthly as appropriate.

The next 2 lanes usually (which you would have used) are the ones with no cashier (ie self-service) - they are normally OK although I have had problems with coins sticking on the way into the bucket/coins bouncing out - there should be a call button there so you can ask for assistance.

I tend to aim for the lane on the far left - the one that most of the lorries tend to use - although the queue sometimes looks larger, it's usually quicker as lorry/professional drivers are more organised and the space one lorry takes in a queue often equals 4 small cars. You just don't want to get stuck behind some old dear with a blue rinse driving a 92 Nissan Sunny from Carlow - you know you're going to be there for a long time....

Hope it hasn't put you off!