For city centre hotels, The Clarion Hotel is lovely and centrally located with beautiful views over the Shannon river.This is a 4 star hotel.
If you wanted to go out in the county a bit. The hotels in Adare are nice and the surroundings are lovely. This is about 10-15 minutes drive from the city. The Woodlands and The Dunraven Arms are nice 3 and 4 star hotels.
Peadar