hiya, theres loads to do it just depends on your interests, there are plenty of museums, art galleries, if you like books then check out dublin castle for some of the rarest oldest books, there are the usual site seeing tours by bus, the guinness factory, the jameson one, loads of shops,
if you let us know what interest you we should be able to pinpoint what will be open etc...
The Book of Kells is worth a look at Trinity College
Also, IMMA (near Heuston Station) - IRish Museum of Modern Art - very cool!
Grafton St. & Wicklow St.(on the Southside) & Henry St. (on the NOrthside) for shopping
Don't leave without seeing Templebar - really cool spot, lots of weird little shops, pubs, and cafes. Urban Outfitters is there also.
Check out the Epicurean Food Hall for all types of weird and wonderful food. Go to O'Neills on Suffolk St. for a proper Irish feed. The Tourist Office is right across the street....
National Art Gallery (Merrion Sq) - you could spend a whole day there.
Got to Butlers Cafe (there;s one on Wicklow St. or Nassau St.) and get the Hot Chocolate.....divine!!!
There are lots of interesting bars and pubs down along the quays depending on what you like.
From an architectual or aesthetic point of view Dublin probably isnt going to blow you away but there's lots of fun to be had there.
Hope you enjoy it Jess!