I've been to Dubli two times and I love this city. The best thing to do is to buy a ticket for the hop-on-hop-off bus which will take you to the most important sights. As the ticket is valid for the whole day, you can choose yourself how long time you want to spend on each sight.
Besides that, Trinity College, Grafton Street and Ha'Penny Bridge are worth a visit.
And don't forget to have lunch in one of Dublins many and old pubs!
I guess if you arrive with a cruise ship there will be shuttle buses. Or else a taxi would do d job.
I do not have any specifi restaurants to recommend, but as I said before - a lunch at one of the pubs, preferably outside the tourist tracks, would be a perfect way to inhale the Irish culture. Every pub offers a number of dishes which can compete with any restaurant.
Went to Cobh (which is the port of Cork and approx. 20km from Cork) last year. The station is directly at the pier and trains leaving 9.30, 10.30, 11.30 ... and back 11.00, 12.00...
Time to and from cork is 24 min.
I had an organized tour to Cork and Kinsale and our time was very limited so we didn't left the bus in Cork.
__________________
AIDA (1996) ArosaBlu (2003) AidaBlu (2004) ArosaLuna und Radiance of the Seas (2005) Amadea (2006) Alexander von Humboldt (2007) Amadea (2007)