To see the spectacular views Ireland has to offer you will need to drive the "real" roads of Ireland. You might find that they are narrow, twisting and bumpy, but you won't notice too much with the amazing scenery surrounding you.
It may take a little longer to get to your destination than you would expect. You should expect to cover about 40 miles/ 64 km an hour. This is due to some traffic, but on the more rural roads you are likely to meet a tractor or even a herd of cattle or a flock of sheep.
Signposts can get scarcer in the more rural areas, off the beaten track, so feel free to ask a local for directions, people in Ireland are very friendly and only too happy to help.
Motorway tolls in Ireland generally cost between €2.00 - €3.00 and can be paid at the toll gate with the exception of Dublin's M50 barrier free tolling. More information can be learned about this here
Care on the more narrow roads should be taken, you never know what is around the next blind corner. It is also wise to familiarise yourself with the rules of the road. In any case, take it easy and drive slow, afterall, you are on vacation, so enjoy it.